Halo 1 Combat Evolved PC Demo Help

I need heLP! I have COmbat evolved the demo for pc but I impored some new maps and everything but where do I go to get my maps? I went to multiplayer and its the same maps!!! All I se is Blood Gulch Blood Gulch! I WANT NEW MAPS! I jst got new ones but how do I play them on multiplayer? Remember, I have the demo! And if theres a problem wiht that then how do I get Halo 1 Combat Evolved for free for pc?

the only way to get it free is illegaly pirate it.
I think the demo should be fine, puting new maps in is kind of a tricky process, goto www.halomods.com they have everything you need to know about modding halo. at halomods register and goto the forums, that where all the goodies are