If you are heading out to the coast, check out SpaceView Park in Titusville. It is a really nice park and it is FREE. It fills up, but not as quickly as I had expected it to. You can get there 2 or 3 hours before the launch and still get a great spot. They have live feed to mission control so you can hear what is going on, there are restrooms, souviners, etc. It is really nice out there. You are directly across the Banana River from the launch site so you can see the launch very well. Here is the link to the directions
http://www.spaceyideas.com/spaceview.html from Disney you can take I-4 east to 528 which is now the Beachline...NOT the Beeline as reffered to in the directions and then follow the directions from there (this is a toll road, so make sure you have some $$).
We saw a launch from the NASA Causeway, it was so cool, but it cost a lot of money that you are not refunded if they scrub. Spaceview park, while a little further away has a great view and is a very nice area to picnic or hang out while waiting for free.
As others have mentioned though it takes about 45 minutes to get out there but plan for up to 4 hours to get back. First time we went out it took 4 hours and 15 minutes to get back, second time it took 1 hour. It is not as bad if you are prepared.
PS (happybirdsfan) I sent you a Private message with some shots we took of Atlantis

Enjoy!