I haven't been to the Decatur Library, so I don't know how their genealogy section is.I do know that The Huntsville-Madison County Library has a whole floor dedicated to genealogy.....a treasure trove.Huntsville was the territorial capital until 1819 and their records have NOT ever been destroyed.Also, Wallace State Community College in Hanceville (Cullman County) has extensive genealogy materials for Alabama from what I have been told.
I have just looked at your posting history.Have you looked at the Morgan County cemeteries I have posted at the USGENWEB Tombstone Project, Morgan County page?Several of the surnames you mention are in those lists....don't know if the specific given names you are looking for are there, but some of the surnames are.I've posted 4 small family cemeteries there.The old Morrow cemetery contains the remains of a 6th Great Grand Uncle of mine.....I descend from a brother of his buried in Logan County, KY.They came out of Carolina in the early 1800s. As far as I know, I'm not related to anyone in the other cemeteries.
I have lived in Morgan County for the last 15 years, but I am a native of Marshall County.If you want to contact me by email, I will try to meet you guys, on a weekend you are here, and point out some old cemeteries, etc.A lot of the surnames you mention are still around and place names named for the surnames for sure, i.e. Tapscott Road and Gandy's Cove.