....and back to the original question...
I looked into this a couple years ago, thinking I'd work something with my Asus eee. Some lessons I learned:
The mic inputs are really crap. Unless you can somehow internally change them to line inputs, you're going to be putting the signal through a really piss poor amp and you'll be adding a lot of noise. Not to mention very little dynamic range in your recording (which means at any given volume, the soft sounds are inaudible and the loud sounds cause overload). I tried running my CChurch preamp into the mic in, and it made a significant improvement, but even then, a lot of noise was added. People were looking to crack open the eee and try resoldering the leads since it looked like the soundcard used had a line-in option, but I never followed up to see if that was done.
So, the first question I had was how to get the signal into the computer. One alternative is to use a PCMCIA card, but since you referenced a netbook, I'm guessing this is not an option. The mic in is sucktastic, so that's out. That leaves the USB. There are a number of USB-in solutions that people have referenced, and they range pretty dramatically in price depending on the mics you plan to use. Some are a combo of preamp and DAC, and there are a number of all-in-one solutions, mics with built in preamp and dac that just plug into a USB port. I tried these out:
http://www.sweetwater.com/store/detail/MicPortPro/ - worked pretty good, decent noise level, ran 100% off USB, but could never get two to work at once (stereo) - I think the USB bus was not wide enough to handle 2x 24/96 signals. It would run 48v phantom mics. At $150 bucks each ($300 for stereo) might be more than you want.
http://www.sweetwater.com/store/detail/Snowflake/ - looked like a good solution, but the case was metal so very heavy. I forget if I was ever able to run 2 at once though to get stereo, but I don't think I did. There was something about how the two devices conflicted or something. Wiser USB-heads tham mine might have prevailed though. If you're OK with mon, this moght work.
I'd do search on USB stereo microphome and see what you get. Here's Sweetwater's list, for reference:
http://www.sweetwater.com/c981--USB_MicsSomething like this might fit the bill, but I have no idea about sound quality:
http://www.amazon.com/Apex-Apex188-Condenser-Microphone-Shockmount/dp/tech-data/B001E0DDLI/ref=de_a_smtdGood luck!
Mike