CLE was my home base for 20 years. Great little airport, really easy to get around. They've got some construction going on at the moment. The only decent bookshop is down the end of C (beyond the PC), but that's in the Continental wing anyway. Also, I'm a fan of the Great Lakes Beer Company (pretty nice local brewery that does a good range). If it works for them, encourage them to stop at the Great Lake bar just opposite the PC, Burning River and Dortmunder Gold are my favourites.