Saw $250 flights out of Orlando today.

There is no cheap St. Pete/Tampa to Orlando transportation that I'm aware of. Someday there may be high speed rail, but that plan looks like it will take a long, long time to come to fruition.

Rental agencies often need cars in Orlando and you can sometimes get a cheap one way rental with no drop off charge. I've done that before to get to the Orlando airport cheaply and quickly.