hey i put my stereo in right and after that when i put parking lights on the stereo would turn its self off now the parking lights dont work and the stereo stays on i think a fuse went for the lights any help?...

u have most likely hooked the park light wire to the earth wire on the stereo therefore bang goes the fuse. as for it staying on check that u have wired it up correctly.

as said above, check your wiring
you may have wired the power wires wrong

check your wiring
you may have wired the power wires wrong
ditto!
what gen is you vehicle and what make/model h/u?

be sure to checkout - http://www.aussiemagna.com/forums/showthread.php?t=52841 and
http://www.aussiemagna.com/forums/showthread.php?t=32761.

I would have expected more to go than just your parking lights. Everything else ok?

Can you elaborate on when parking lights were on = stereo off and now parking lights don't work? Was that at the same time, after switching off the ignition, etc?

Do the headlights work still, wipers, lighter/12v socket?

I think the best investment you could make here is a cheap DMM (digital multi meter) from Jaycar, Dicksmith, Super cheap or at very least a 12v test light. It will help you with identifying what goes on when without blowing expensive equipment or fuses (that haven't already been blown :D )