Cherie, thanks for that. I've read Perry's guide and several other ones that I could find as well and it's been very helpful. I guess Adwords is like a lot of things - once you've been doing it for a while and got the hang of it you wonder why you couldn't see the wood for the trees in the first place.
As it's a new thing for me on the various sites I'm going to try Adwords on I suppose it'll be suck it and see - just try to invent as many relevant search words and phrases as I can and then play around with bid/budget figures and see what happens. Seems a bit hit and miss though