Georgia has some great places to ride. There is a book by Jim Parham with maps and directions for 25 road routes in North Georgia that is a good investment. The rides in North Georgia range from sort of easy to quite challenging. The ride up Brasstown Bald, for example, is one of those things you want to do only if you are a good climber and in good shape.

In the southwest corner of the state, near the Alabama border, there is the fairly bike friendly city of Columbus. Around town and Fort Benning are many nicely maintained and scenic roads. Further east is the flat land around Plains and Americus where President Carter grew up. Riding around there is pleasant in spring and fall, though pretty hot in summer.

As bbeck mentioned, the Silver Comet runs from the suburbs of Atlanta out to Alabama, where it meets the Chief Ladiga Trail. It is a rails to trails closed route with good facilities along the way. Very peaceful and easy once you get out of the congested first 4 or 5 miles.

There are great bike friendly communities in a line between Stone Mountain and Downtown Atlanta. Roswell, north of the city, also has in recent years begun to attract cyclists. In South Fulton County, south of the city, is a completely wonderful area that includes the community of Serenbe. Cycling there is amazing. Because the road conditions are so good, the area is known as "Silk Sheets" to Atlanta area riders.

The problem with cycling in Atlanta is that for the most part, unless you live in one of the nice riding areas, you generally have to put your bike in the car and drive to someplace to ride. You have to be extra careful about cycling in most of the Atlanta metro because the roads are congested, the culture is still somewhat resistant to cyclists, and the drivers here are mostly below the national average in skill, courtesy, and awareness. It is, for example, rare to see drivers using their directional signals at all, much less correctly.

Good luck with your move!