If you've got Georgia on your mind, there are several very useful collections of online archives covering the state's history and records.
Virtual Vault is a very varied collection of digital materials, as should be evident from a quick scan of the titles:
Most of the collections belong to the Georgia Archives proper, but a few come from other sources, such as the Georgia Capitol Museum. The collections include a smattering of family history information, but most archived vital records in Georgia have not yet been digitized.
Georgia State University has two digital archive collections, one devoted to university documents such as research papers, conferences and the like, while the other, the library's Digital Collections, include numerous historical items broadly related to the state of Georgia and to the interests of some its prominent citizens:
The last resource (and from the looks of it, the largest) is the Digital Library of Georgia, a collaboration between the University of Georgia and numerous libraries, agencies and nonprofit organizations. Their list of content is impressive:
Whew! Happily, their search function searches all collections at once. Have fun!