I recently upgraded my Sonar X1 to Sonar X2 and am thinking about a new soundcard. Unfortunately, I'm using a laptop so my only option is to buy as USB-style external soundcard (I don't have an ExpressCard port). I don't know what to look for, but I would like something that would boost my sound capabilities specifically when using Sonar. Any suggestions or recommendations would be greatly appreciated. Here are my computer specs:

Operating System: Windows 7 64-bit Laptop: Dell - Intel Core i5 (2.67 GHz) - 8GB RAM - stock sound card (IDT High Definition Audio CODEC, Intel(R) Display Audio).
DAW: Sonar X2

Depends on your needs.

Are you intending to record full bands, or just yourself?

I would take a good long look at some of the Presonus Audiobox range - they sell a variety of configurations, have rock solid drivers and operate at very low latencies.

And they are not overpriced

Focusrite works for me. I haven't looked at their prices lately so I don't know if they're overpriced.

I know this was ages ago, but I realized that I never responded to your suggestions. Thanks for taking the time to respond. I ultimately went with a PreSonus AudioBox USB interface and it's been working well for me for the most part. Occasionally I'll get some static and I must unplug it and replug it back in for it to correct itself. It's a rare occurrence thankfully. :)

I've also updated my signature with my current system and hardware.

Welcome back.