I'm going to be selling ad space on a radio page which gets 300 hits an hour and is a solely student demographic. I was just wondering if there is anyway I can work out how much to charge to local clubs/student attractions for advertisement.
I would start with something like Google AdSense. It allows you to have some advertising up until you are able to land advertiers yourself, and by seeing how much money you're getting from AdSense, you'll be able to judge how much ads in your niche go for.
Very generic rule of thumb is to sell for double whatever AdSense gives you.