If you go to Clearwater we like the beach at Sand Key. It is in Clearwater but just South over the bridge from Clearwater Beach. You have to pay to park but it is much less crowded.
Another nice beach is Howard Park in Tarpon Springs. It's a county park with picnic areas and play grounds on the main land then the beach is on the barrier island.
The very best beach in that area IMHO is Caladesi island, you have to take a small ferry from Honeymoon Island state park in Dunedin.
http://www.floridastateparks.org/caladesiisland/.