Just in case you're not subscribed to the Franklin County mailing list (a couple of people have answered your "gatewayed" message)-- The two best places to do research in Franklin County are the Columbus Metropolitan Library (main branch), at 96 S. Grant Ave. in the heart of downtown www.columbuslibrary.org/
They are open 9-6 on Saturday and have underground parking at a very reasonable rate. Be sure to ask to see the Green Lawn Cemetery records on film as there is a George Seibert buried there (you might even get to the cemetery if you have time as it isn't far).
The Ohio Historical Society Archives/Library (the state archives) MIGHT have even more that will help you with Washington County (Marietta). Before going it's a good idea to review the FAQ as there are a lot of restrictions - http://www.ohiohistory.org/collections--archives/archives-li...
Personally, I'm glad that I live in Franklin County as it's a great place to do research for the whole state and there are lots of helpful staff members just waiting for your questions.