Being a frequent user of the Cincinnati Airport...
I supose I should start out by asking which airline you are taking.
If it's Delta, Northwest, Continnental (or any of those airlines regional partners, like Comair, Mesaba, NW Jetlink, etc) you will be in Terminal 3.
Terminal 3 is where you want to be, preferabbly in either concourse B or C. (C is all Comiar I beleive)
Moving between consourses A and B is quite easy with an underground train found at the center of the B concourse and at one end of the A concourse. Concourse B has a full food court and a few table service eateries (like Cheers!, themed after the tv show), concourse A has some dining but its more limited. I think they put the NWA and Continental flights in A.
None of the concourses alone are so large as to make you fret. A and B are just long hallways, easy to navigate. C is a bit different with a food court in the middle, and gates on four arms off the main hub. C is also not connected to the train. Getting to C from the main terminal, you ride the train to B. At B there is a bus that will take you to C. Little used fact is there is also a bus from C to A, (or A to C) that is often a lot less crowded than the B bus.
Also, if you are flying in on an International flight, the customs office is in B.
Now if you aren't flying one of those carriers, you may be in terminals 1 or 2. They aren't bad, they are just old and small, offer a lot less ammenties. In Terminals 1 or 2 all the eateries and shops are 'outside' the security checkpoint, whereas in the newer terminal 3 there are a couple places outside the secured area, but most of the stuff is in the secured area.