I bought the Avenge at a local carpet cleaning business, but I'm sure it can be found online. (I googled it and found this website -
Avenge Carpet Spot and Stain Remover). The Avenge is actually for tough to remove spots, and when I use it with a small carpet shampooer it works like a miracle. You might want to treat any spots with the Avenge, then use something like Rug Doctor all over afterward. It has been especially helpful during house training too.
I absolutely abhor carpet! If I could I'd do my entire house in hardwood & tile.