I like the Alesis 3630. It's inexpensive and is discreet and does a great job. Hope this helps ya out. I'm a basement musician looking to use my PC for doing some recording. All you'll need is a full duplex sound card meaning you can monitor the input and output at the same time.
Most newer cards are full duplex.
You'll need a card with stereo inputs and outputs. You'll need some sort of mixer to feed signals into the card. You can use any LINE output to feed your sound card. Be it a mixer or a LINE output of a home stereo receiver. You will need some software.