You may want to check out the Mackie Onyx series, which combines the audio interface (sound card) with the mixer. I think there are 8, 12, and 16 channel boards. Bunch of features. Worth looking into. Not sure about pricing.
For mics, you'll probably want a decent Large Diaphragm condenser microphone for your vocals and guitar. If you're planning on playing heavily distorted guitar through an amp, you may want to go with a Shure SM57 for that, which is a dynamic. Runs about 99 USD. Worth every penny.
I'm assuming you already have a recording program since you didn't ask for rec's on that, but if you don't, let us know and we'll try to get you sorted.
Storm made a good point with saying a MIDI keyboard would be a good investment. If you're planning on utilizing any software synthesizers or virtual piano programs, even drum software... then having the ability to physically play the instrument via a MIDI controller/keyboard is the best solution if you want any kind of human feel, without painstakingly editing MIDI notes to imperfection.
Let us know how this does you.
__________________
|