Another tip on placing your own cleats -- I am anal about having the bikestore (if you know someone good), fitting your cleats on your road bike. The guy I go to has improved my technique by fitiing my cleats and road shoes properly (they also will "shim" the cleat to correct for improper form -- ie, I used to splay my knees out too much, esp when I got tired).

On a spinner though, DIY, put your shoe on and with a marker, put a small tick at the point at which your "bunion" bone (don't know what it is officially called!!) center hits the shoe -- you kind of feel around with your fingers. Take a look at your cleat, and you will see like a formed line in the side of the cleat. That line should line up with that tick mark when you place the screw down the cleats to your shoe. Also consider using some of the lock-tight (a blue goo you get at the bike store) on the screws which will keep the screws from unscrewing prematurely.

Hope this helps!