In Britain (I am sure it is the same in the states) we have online job vacancy databases which you can search. They have a wealth of data about salaries for different roles, you can usually get a fair idea of what you can ask for by browsing them.
I have seen one of them (might have been monster) which actually lists salary expectations for a range of jobs.
Wages are extremely variable geographically. What is normal in my city (Waterloo) is tripled if I drive an hour down the road to a larger metro (Toronto). Your best bet is to chat up some people in your town who already have similar jobs, and ask if they're willing to cough up their numbers.
There's a social taboo about discussing "what I earn", which is kind of silly but at times practical. If you can crack that, you'll get a good idea where your expectations should fit.
Last time I checked one of those salary expectation lists, the data was many years old and the numbers were far too low. Your mileage may vary.