There are thousands of miles of coastline and many, many, many excellent beaches. Small towns, big cities and everything in between.

I've never heard Sao Paulo described as one of the two best tourist locations in Brazil. If you mention Rio and SP because you've heard of them and not other places (as is the case for many people), you should get a guide book. A good investment, given the money you'll end up spending on the whole trip. Brazil is the size of the continental United States. Be expected for high prices.

Have fun.