i am trying to figure out what i need to run my bass through the computer so i can record bass riffs with really good sound. please help. thanks

no one knows?

You need a pre-amp and cables.

What do you think about this:
http://www.alesis.com/multimix4usb

I think it works well. I've seen friends of mine use and sound quality is ok. I try to keep it a little cheaper. First i record the riff with a Zoom H2 (http://www.samsontech.com/products/productpage.cfm?prodid=1916) and then copy it from the SD to my hard disk. Very good sound quality. But that gadget is mainly for live purposes. Good luck man.

Line 6 toneport is the simplest cost efficient way imo.