James,
 
Lynn Scheu's book suggestion is good, but out of date. The best buy is now:
 
Feldmann, Rodney M., editor, 1996, Fossils of Ohio: Ohio Division of
Geological Survey, Bulletin 70, xx + 577 pages.
 
This rather large book is well illustrated and includes chapters on all
kinds of Ohio fossils for the general reader. You can buy the book for less
than 20 dollars at:
 
Ohio Division of Geological Survey
4383 Fountain Square Drive
Columbus, Ohio 43224-1362
Telephone (614) 265-6576
Email [log in to unmask]
 
Since you're in Columbus now, this might make a nice visit for a rainy day.
Or it can be purchased by mail, probably with an extra charge for postage.
If you do visit, tell me what the Ohio Survey is like. I work at the
Alabama equivalent, which has a larger staff (more than 80 people), and I'm
curious about Ohio's.
 
Andrew K. Rindsberg
Geological Survey of Alabama
Tuscaloosa, Alabama, USA
 
P.S. The most common Upper Ordovician brachiopod that is shaped like a p
ecten in Ohio is Rafinesquina, which was named to honor the bizarre
naturalist Constantine Rafinesque. Rafinesque was a very enthusiastic
scholar, but pushy, and he irritated his peers by rushing hundreds of
species into print in a few words without illustrating them or depositing
type specimens in a museum. After a while, journals stopped accepting his
manuscripts, and he published them on his own until he ran out of money.
Biologists are still trying to sort out the mess. Rafinesque has been
getting relatively favorable press these days from sentimental biographers,
but believe me, if you've ever actually had to deal with a person like
this, and I have, you'd agree with his contemporaries' opinion instead. The
phrase "loose cannon", from a hot cannon rolling around the deck of a ship
during the confusion of battle, comes to mind... But I digress.