Last year we caught the Jays and Tigers at Lakeland, and the Braves and Nationals at Wide World of Sports. They are each great ballparks -- I love spring training because it takes you out of the 'arena ball' kind of experience. As I recall, we paid about $30 a ticket for seats at the top level behind home plate.
I joked with DH that we were able to see pretty much every pitcher the teams could dress.
At Wide World of Sports we had a car, which was helpful because it's hard to get to otherwise. If you're staying on property and don't have your own transportation, I'd take a taxi.
On an earlier trip, we stayed at Vero Beach and drove up to Space Coast Stadium to see the Nationals and Tigers. Weird location for a ballpark, but its easy to get to.