I second the M-Audio USB Transit...I own one.
While PCI cards are good...that means you either need long rca cables..or locate your gear next to the PC, which puts out a lot of noise. The magic of the M-Audio is that it comes with a 6ft USB cable...but your limitation is the same as any other USB device. So you can locate the unit near your gear, utilizing short cable paths...but have your PC located away from the entire process.
The problem with onboard cards, even some of the better ones...is that down at the noise floor...sometimes just below the noise floor, you get digital interference...and onboard cards are famous for this...it's like a pulsing....and it tends to get worse when you do something like move the mouse or use the CPU. I haven't heard them be that offensive since sometime int he late 90's, but the point is, even the XFi I had...down around the noise floor...it was there.
An external device is ALWAYS preferred vs an inboard card...even if it's a seperate card. The components aren't physically shielded that well and just around a bunch of noise.
Software wise...there's Audacity...but my biggest beef with it is that being a FOSS program...there's no money being dumped in to development...so it's a wonky program to use. It's not really a dedicated editor as much as it is a time-line editor...an editor that combines the functions of a sound editor in a multi-track enviroment. It has nothing to allow it to function as JUST an editor...so you're stuck wasting resources you might not even use. The effects...they're ok....but they're FAR from professional quality...mostly textbook implementations of FFT that's taken from already existing code source.
There's nothing exciting going on other than that it's free...and that happened because of the perceived gap and the fact that a lot of these methods had eventually been public-domained...reversed engineered...or what have you. I mean, they're really nothing groundbreaking. A friend showed me something in Audacity that he got all excited bout and all i could say was "I was doing that years ago in Adobe Audition".
Mostly, my beef with any "high-level" open-source audio application is just the fact it can't be that well developed. Not many people who are really good at DSP/FFT coding are going to donate their time to coding complex effects...and the people who are..just aren't that good at it. I think it's great...to a degree...it's getting the tools in the hands of people who can't afford them...at the same time..it's giving them sub-par results that if people start to use for serious nature...the overall quality of music is going to go down.
For just basic recording...splitting and such...it's a fine program..however it seems to have an issue of it will not actually record 24-bit audio from a 24-bit source (which the USB Transit is)...it says it is...but it apparently isn't interfacing properly...not sure if they fixed that bug or not..but last time I used it, it wasn't recording true 24-bit.
Another fine piece of software out there is Goldwave. It's a Windows only editor...and it's actually what I started using 12 years ago before there were any open-source editors. It's effects are, honestly, just about on par with Audacity..although it's editing interface is a bit more advanced and some of it's effects are just excellent. Again, a lot of text-book implmentation..but being a commercial program, there's incentive for the developer to work on it and improve it. It's also got the best licensing of any paid-for editor...there's a fully functional demo that will allow you a specific number of commands so you can fully try it out (saving included). $19 for a one-year license, $49 for a lifetime license (I can attest, I paid the old registration rate of $35 back in 1997 and I've never had a problem with the new versions). I mostly haven't had a lot of Audacity expierence because I started off with Goldwave...however, i've used it, I know it's limitations..and one can do a semi-decent vinyl restoration with it....probably about as good as what one can do with Audacity without all the extra confusion. Considering the problems I've had in the past recording 24-bit with Audacity, Goldwave is my go-to program for recording audio in to the PC.
If you're interested in doing full-blown restorations...taking out the crackle..noise...what-have ya...then I highly recommend Adobe Audition. The former Cool Edit Pro and full-fledged DAW isn't as pricy as Pro-Tools ($350), but it does just about all the same functions. It's various effects are really top notch and the plugin support for both it's own format, DirectX and VST is amazing. However, I don't use Audition alone..I also have the plugin ClickFix for Audition for doing a lot of click filtering...this little plugin has to do about the best job I've ever found for getting rid of the big offensive stuff quickly. Sure, it's an extra $35...but it's well worth it and rather than doing the simple interpolation around a click...it'll recreate a segment of audio to fill it in...and it does an amazing job. If you want to go all out...that's the route.
Also on the all-out route...there's Izotope RX. It's a HUGE resource hog, but it's effects are also seriously up there quality wise...I don't know exactly how much it costs...my copy was given to me by a studio guy to evaluate for them....it's really good...but takes a lot of time to process audio depending on your CPU speed.
Really, regardless of what software route you have...get a good sound interface first. I know an internal card is probably attractive....but...putting a PC next to your pre-amp isn't...and if you want to keep short cable runs to the sound card, that's kind of what you have to do. With the transit, I can put a 12ft USB cable on it and keep plenty of distance between the digital and analog gear...and they play nicely.
Ok, but samples...I'm sure you want samples of what the transit sounds like. I don't have any 96/24 samples online, they're simply too large for me to store online. I do however have some samples of vinyl transfers I've done with my Yammy PX-3 with the Shure M97Xe with the "damaged" stylus...you know, before I broke it (talked about in another post)
http://jay.is-lost.org/panamaredvinyl.mp3 <- this is a straight off the vinyl recording. I've done nothing to this file to clean it up/master it. this is the audio as it was recorded by my transit after it passed through my Denon's pre-amp. The only thing I did was a very careful and optimized downsampling to 16-bit with a 96khz noise shaping (pushes the noise shaping above 30khz) and then downsampled from 96/16 to 44/16...does a very nice accurate downsample with the noise-shaping noise getting removed. Compressed to 320kbps mp3 for transmission purposes.
(I have provided these links as EXAMPLES only. I do not publicly condone piracy of music. I've simply uploaded these for demonstration purposes. If anyone feels these links should be removed, let me know and I'll gladly remove them. Again, not here to give people music...but here to demonstrate what can be done. Thanks)
http://jay.is-lost.org/panamaredmaster.mp3 <- this is a fully restored and mastered copy...done from the exact same file and recording the first mp3 was done at. this is after I've done clean up and adjusted the EQ and such to compensate for any drift...cartridge timbre and to give it a nice rich sound. I'm not revealing my secrets on that one...however, this is the end result of what one can do with a Transit and Audition and a few hours of time.
http://jay.is-lost.org/cantina.mp3 <- electric moog's version of Cantina Band from star wars...this is a "mastered" copy after restoration.
http://jay.is-lost.org/bst-lucymcevil.ogg <- This is a track taken off the BS&T - Greatest Hits LP. Again, this is after restoration and mastering. I copied this to ogg because the people I originally sent it do happen to do a lot of ogg...but I'm sure if you want to hear it, you should be able to.
I seriously highly suggest you getting the Transit...for the money (about $80 - $90), you cannot find a better DAC/ADC (ok, it's a codec chip) anywhere. Supports standard sound input methods as well as having it's own ASIO driver. But if anything, you can locate it close to your gear while keeping your PC far away..that's why I highly recommend it.
i wish you luck with your needledrops.