Mears has busses that run out to Kennedy Space Center. Mears is the bus
company that runs from the airport out to the disney resorts. You could check with Tiffany Townecar OR Quicksilver, but I think that may be too far for them.
Look on the disney website for the Mears info.
Look on at tiffanytowncar.com
OR this website (wdwmagic) for Quicksilver info.
You will enjoy KSC, I visit the center every other year OR when they
have a shuttle launch and I can get down there!