there are several cleaners like that. they reportedly work well but i have not tried them. seems to me that one is available at Napa for around 15-20 bucks, but i could be wrong (pretty sure about Napa, not sure about price).
not sure what you meant by 'tell me more' but basically you would disable the fuel pump and run the car off the contents of the cleaner (via the schrader valve that you mentioned).
good luck.