The Georgia State Archives maintain an interesting holding of materials, and it might be worth a trip to investigate what they have.
The Archivists maintain almost 30,000 reels of microfilm. These reels contain Georgia governmental records, selected U.S. records, Georgia county records, tax digests, private papers, church records, cemetery records, newspapers, genealogical records, bible records, books and periodicals, selected out-of-state and foreign records, federal census schedules, Georgia Confederate service and pension records, Colonial, Headright and Bounty land lotteries, 1.5 million land grants and plats from 1755 to 1909 and a few municipal records.
They also have 10,000 county and state maps. You can see all of the county boundary changes that have taken place since Georgia became a state. This can be very important when you are trying to figure out which county courthouse holds the records that you need.
For example, McDuffie County was formed in 1870 from Columbia and Warren Counties. If your ancestors lived in the Fort Creek area prior to 1870 would you know which county courthouse to visit? (The answer is the Warren County courthouse).
You can also find maps that contain place names that do not exist anymore. Towns come and go, and it is common to find a name of a town in a document that you can't find on a current map.
The Georgia Archives is also a library containing books and periodicals specific to Georgia history. Many of these publications are out of print and not available anywhere else. The Georgia Archives does not participate in the interlibrary loan program because of the great value of these books. I don't know of any library with major genealogical holdings that participates in the interlibrary loan program, so the only way to look at these books is to visit in person. This collection is searchable.
They maintain an index of available military records, court records and Justice of the Peace records. They have collections of documents and information bundled by surname. They have church and cemetery records listed by county. Old church records are very valuable. Births, deaths and marriages were recorded before it was mandated by the government.
The archives house three different photograph collections chronicling the history of Georgia and its personalities. They also have a large collection of CDs available for viewing. These are indices to census records, marriage records and the social security death index.
There is a partial online card catalog of the Archive's holdings at http://www.sos.state.ga.us/archives/index/sa.htm. If you have computer access, this can save you quite a bit of time. You can make a list of the resources you want to view before making the trip to the Georgia Archives. The staff is very knowledgeable, so take advantage of their help. You can contact them by email at firstname.lastname@example.org.
The Georgia State Archives is located at 5800 Jonesboro Road, Morrow, GA. You can contact them at (678) 364-3710. Their hours of operation change from time to time, so it would be a good idea to call ahead.