Clock spring will sound like it's coming from right behind the steering wheel, because that's where it is!
The u-joint shaft assembly will make an annoying clicking sound that seems to be more audible in the car and is a common (and expensive) problem. The green plastic seals (no.3, lower diag.) can make noise but a bit of silicon or similar spray should help with diagnosing. I think it's pretty rare for the bearings to give any trouble.