ive got an issue with my bike well lots but im addressing one at a time

basically bikerz noticed my rear light wasnt working (not the brake light the side light) so checked the bulbs and checked all the wires and earthing upto the fuse box no problems as all, i rode my bike a bit then one day i started it up and the front lights stopped working all together! but the back light started working!? ive got no main beam or sidelights, i checked the bulbs one of the siidelights has blown but the other is fine,
thanks to jamz ive put a different fise box in as i thought this might be the problem as mine wasnt to clever but ive still got the problem and am all out of ideas, so any help would be much appreciated,
thanks
Leanne