If you go to Anna Maria island, there is a restaurant called The Beachhouse, which is very good. It is right on the beach and their food is delicious. The seafood is fresh and they also serve some non seafood dishes too. I don't know how busy it is this time of year but in the summer it gets pretty busy.
You must try a restaurant called Ezra 5629 Manatee Ave ezracafe.com. The chef is also the owner.
For Seafood - I would go to the Sandbar, Rod & Reel, Chart House, or if you don't mind chain restaurants - I love Bonefish Grill.
For a good hamburger go to Councils downtown Bradenton across from the court house. It is a dumpy place but the hamburgers are great!!!!
I am not into Sushi - but people I know love the restuarant next to Publix in the Bayshore Gardens shopping area. Sorry - no clue what the name is.