http://www.centennialpark.com/images/Downtown%20map.pdf
Everything is within walking distance.
We stayed at where it says Peachtree plaza, in the topish rightish corner and it was either a 15 minute walk from my room to my pits, or a 10 minute subway ride.
The only reason it was 10 minutes on the subway is because you had to go south, then west and transfer to go that west.
It's not bad once you get used to it, but just don't forget which way you are going, or you may get into some trouble with your teammates for leading them off the correct train...
Also, a map of the actual Georgia World Congress Center (pits) and the GA Dome (stadium) complex can be found here.
http://www.gwcc.com/images/gwccmap.pdf
Good luck in 2005, and if you need help navigating Atlanta, just ask any team you see if they were there in 2004. BY three days of being in Atlanta, you pretty much know your way around.