Mountain Biking - one inch forks

Hi everyone, I'm new here and couldn't find the answer to my question already posted, so forgive me if you've heard it before.
I have a department store mountain bike which my parents bought for me a while ago. I work at the LBS, and I got some okay components dirt cheap. (deore der's and shifters, some alright stock wheels from someone else's bike). However, the bike was made for a one inch threaded steerer. The frame's not heavy, and I don't want to chuck a gift from my ma and pa, so I've been trying to find a decent one inch threadless susp. fork, and my boss at the shop says they can never manage to get the RST Omni. Does anyone here know of a fork that would work? While we're at it, can you recommend a decent crankset for kind of cheap? mine are stock, and heavy.
Oh and I'm trying to change the fork because my current threaded-to-threadless stem adaptor is heavy and not very adjustable and ugly. The bike is a mongoose "serif".
I think that covers everything. Anyone able to help me?

I hate to say this, but as you know your options are really limited. You can probably find a low end Marzocchi in a 1", but chances are the travel on it will still be way too much for your X-mart bike. Your best bet is to save a couple paychecks and buy a bike off the shop floor. (Most shops give a healthy discount to employees, but the specifics are not something to be discussed in public) Save the X-mart bike for the ride to work and ride it until it falls apart.