Countdown Clock is running for STS 135. Weather permitting, Space Shuttle Atlantis will launch Friday morning, July 8th, for the last time, and the final flight of the Shuttle Program.
She will go into orbit for twelve days, returning on the 20th of July. Her main goal for this mission is supplying the ISS with one year of supplies.
I highly recommend this website. http://www.ustream.tv/nasahdtv
It will be carrying all conferences, pre-launch activities, and launch.
It will also carry video feeds from the shuttle during the mission, conferences, and the re-entry and landing of Atlantis...for the final time.