Hi Paul
I use adwords for one of my sites, but I am not an Adwords expert from any angle!
It is a love-hate relationship.
When I use adwords for a few weeks, I mostly always start hating it because my campaigns generally just manage to break even. And then I stop my campaigns for a few weeks, again to get attracted to it later after a month or two!
And the cycle repeats...!
-Abhi