let me tell you that i have a bass guitar and i had greats results using guitar Rig, its a good inversion, you can route bass guitars or anything you want there, is the more natural sound you can get if you want a bass guitar sound in you tracks... it sounds pretty natural. Of course you need to have (or borrow) a bass guitar
My podX3 has usb connection to act as an interface for guitar/bass/mic. Also have a zoom multi fx thing that has usb as well. They probably all do these days. Software like guitar rig must come with some interface?
It's money tho, would only be worth it if you're planning on playing in a lot of stuff yourself.
its very easy, you can use a audio interfase or you can use asio4all drivers (they bypass windows routing maze and send the signal direct to your soft) ive done it with great results. you can download the drivers here http://www.asio4all.com if everything is set properly you should play without feeling mayor latency, i use guitar rig as a standalone app when im practicing with my bass cos i dont have a good bass Amp.
theres plenty of tutorials outthere but if you need help you can ask me.