The absolute best site I have found it

http://www.nasaspaceflight.com/

Nagivate to the forums (link at top of page). There is a separate forum for each of the shuttles. Within the Atlantis forum you will find a "going to launch" topic - great information in that thread and in previous "going to launch" threads on earlier Atlants missions as well as the Discovery and Endeavour missions.

We made two trips over two months and had 6 or 7 scrubs before seeing STS-127 launch in July 2009. We are in the lottery for causeway tickets for STS-135, along with a few hundred thousand others I suspect.

The UpClose Tour is awesome - we took it several years ago when there was a shuttle on the pad a few weeks prior to the launch. When they take you out by the ocean you get a really good view and it is just so quiet and peaceful out there.