If your computer's made within the last 4-5 years, I heavily doubt you have an AGP slot on your motherboard. Sorry to shit on your parade, brad.
But an easy way to see if you have an AGP slot on your system is to look for a brown slot. Magically, these things are always color coded!
Then again, I did have a customer with an MSI motherboard that uses AM2+ processors, DDRII PC8500 RAM and had an AGP slot. It was the weirdest god damn thing I'd ever seen in my entire life.
Please. Don't hate me. I only do this for the sake of avoiding sandy crotches!
But if you have another older system kicking around, it's actually a nice videocard to throw into it to help it be more less shit and sort of up to date!