always get a quote for the entire job in writing, not by the hour.
It's amazing how many people get caught out by not getting a quote/estimate on parts as well as labour.....
In Oz the rates can vary greatly, I've seen some as low as $45/hr (too cheap) up to as high as $120/hr.
A bloke I know reckons (don't know if it's true) that he put his wifes Honda in for a service and was charged $70/hr, then the next week put his BMW in for a service, at the same shop, and it cost him $95/hr - same mechanic. When he queried it, he was told that there was extra training involved for BMW's so they charged a higher rate....he now goes to a different shop.