uhh, well i'm not sure if you will be able to buy a sound card to do all that for less than $200...but you could try getting a Sound Blaster audigy 2 ZS, i just got one from Happydudette when i came to aussie, and i like it! i haven't explored all the features yet though, so i can't tell you much about it other than it has support for a whole bunch of sound stuff, and a whole bunch of ports. (like 6-7)
Sound Blaster is a good brand. Make sure you get the one with the box you can put in front of computer in one of the cdrom "bays" for alot more freedom to hookup things like guitar in your case