Hmm float trip for trout in PA... I would look into the Little Juniata and the Youghigheny near Ohiopyle. I've always wanted to fish the Little J. It's a tailwater that goes through a canyon. Supposed to be pretty good. It is very remote though, about 4+ hours from NOVA. The nearest float trip for trout is on the North Branch of the Potomac in Maryland, I believe.
Most of the great trout fishing in PA is due to the influence of springs on freestone streams or spring creeks. There's the Yellow Breeches, Big Spring, Letort, and Falling Springs all within reach of a day trip. Wading is the name of the game (although not so much in the Letort).
You should also look into float trips for smallmouth bass. The main stem of the Potomac River is pretty good, and the Susquehanna in PA is awesome, and so is the Shenandoah main stem, north fork, and south fork. Canoe trips on smaller mid size streams for smallies are also a blast.