music software

So I've been trying to find stuff on software that lets you hook up your guitar to your computer and turn your computer into a sort of amp. This is something I want just for fun, since buying a big fancy amp right now is out of the question. I found a ton of software, but which is the best and which is the best for the price. i want something that would let me try out a whole bunch of sound affects and has record and playback capabilities as well. Any got any suggestions?

Here's a sound card I was looking at before: http://www.americanmusical.com/item--i-MII-D442--d-4.html
That's the biggest issue you'll have to look into, connecting the guitar to your computer. I believe I saw a couple other cars similar to that one, with less inputs and outputs and for cheaper. Look around www.americanmusicalsupply.com (http://www.americanmusicalsupply.com) and www.music123.com (http://www.music123.com) (don't think I found any at musicians friend). And for a program I'd try the demos at the Cakewalk website. I love Sonar 4, it has a ton of stuff you can do with it. The best would probably be their Guitar Tracks program, but unfortunetly I haven't been able to get any sound to come out of my speakers on playback (could just be my soundcard though). But if you can get that to work, then it's got everything you could want. Comes with different amp simulators that can be customized, a ton of effects as well (since I have sonar and guitar tracks, I can use the plug-ins of both programs on both programs).