Salmon Creek is popular and holds a lot of fish. The outlfow portion of Tionesta is a good one too.
Don't forget Ross Run - usually the week after the opener - a local club stocks it for kids/handicapped individuals, but it is open to the public after the initial stocking.
Lastly, Big Coon. It's not stocked for the opener (something about the pH being off) - but when they stock it the week after (and I think into May) - it can be a hot spot.
It has been known to hold fish well into June/July (if you find the right pools and don't mind getting beat up by jagger bushes {yes, I'm from Pittsburgh})
Late June on Big Coon can produce nice fish if you're willing to "work" for them.
The secret is out..........