You need to decide how many inputs you need to record at once. Also, are you going to mix with hardware, or software?
For example, if you are recording say eight tracks at once, but you are going to do all your mixing in software, then you might choose an audio interface without an actual mixer.
If you only need a few inputs, then why get a mixer? I use an M-Audio Audiophile sound card. You also want, however, to have something to control your monitors.
There are so many options out there--it is a big topic. Do some reading on these forums. However, if I were buying right now, I would seriously consider the Mackie Firewire 800F with the Onyx preamps. Read the review in Sound on Sound.
