any pre-wash stain remover (for your laundry)will work.spray some on the stain and wait about 5 min.spray a little more and use a white cloth ,punch the capet,try not to rub the carpet.for next time home depot sells a product called folex.
You might want to try rubbing the carpet with alcohol. I got a paint stain in my carpet a while back and rubbed it with pure alcohol and got rid of it.