Amy, if you just have a little paint on the carpet, your hardware store or home center should have a latex paint remover in a spray can. One brand is Goo-Off but there are others. Be sure to test this in an out of the way place first. Things like Steve:'s ammonia suggestion and paint strippers may be a little or a lot too harsh for the carpet so test anything before you commit. If you have a lot of paint in small area and if you saved some of the cutting scraps from when your carpet was first laid, a pro can replace a section.