Wafer locks have flat wafers as you look into the keyway (obviously you'll only see the first one). They're pretty easily distinguishible from pins with a bit of experience.
Warded locks are easy to identify from the shape of the keyway, which is the "keyhole" shape (
http://www.gnu.org/software/gnu-crypto/ ... eyhole.png) that little children peek through to watch dirty things. Such a keyhole is going to be either a lever lock or a warded lock... a warded lock is basically just a lever lock without levers.
There's another sort of warded lock found on cheapo modern padlocks... it's also really easy to identify, but I can't describe it. Maybe someone can provide a picture of a keyway.