I just moved here in Sept from Oregon (land of bike paths) and would caution you not to expect good bicycling here.
I was accustomed to biking to the store and work, but I've only gotten out on my bike once in the past two months. Atlanta is alarmingly anti-bike or pedestrian (or handicapped people, for that matter). The few sidewalks that do exist -- the only safe place to ride in most parts of the city -- are grown over or crusted with dirt or end abruptly after a few blocks. Curiously, it is illegal to bike on the sidewalks, but to put your bike on a street with NO shoulder and drivers who seem oblivious to anything on two wheels or two feet, constitutes a death wish. People are so vehicle oriented here that a push just began to encourage kids to walk to school -- they've never done it before!
So, don't expect to be two-wheeling casually here. You have to plan it, and you have to transport your vehicle someplace. I've seen 2 people who looked like they were commuting to work on their bikes, but that's it. Two people in two months.... it's pathetic.
Walking isn't much of an alternative, either -- cars do NOT stop for you in crosswalks even though it's the law, in fact they seem to aim for you. If you have a green signal in a crosswalk, don't expect cars to yield to you. The other odd thing I've noticed is that even pedestrians don't seem to get it here -- most walk WITH the traffic rather than against it, which is something I was taught in grade school.
Atlanta has a long way to go when it comes to bicycling and walking. Efforts are under way, but it appears it will be at least a decade off before any sort of convenient bike path system for commuters is in the works. People here still think of bikes as toys for kids.