Definitely. I bought an adapter at OSH for 10 bucks just this past week. It turns the connector on a 20lb propane tank into the quick connect that the stainless steel performer uses. If you can't find it in the store, call Weber customer service, they should be able to hook you up.
Also, Weber will sell you a new style 5lb tank with the quick connect built in for 50 bucks if you want to go that route. Because it attaches to the cart, the 5lbers are more convenient.
Bill