helpdesk software solution

Hi there

I am looking for a helpdesk software solution for our IT department to keep track on all issues and calls for users about on their computers printers and son on? it should be email integrated and PC inventory integrated and web based in order to be able to reach it on any computer, and of course I am not looking for expensive one?

If anyone has got any knowledge\idea on this issue please reply.

Your help is very much appreciated

TIA
JoelB