Look for used ones...those things last forever with some decent maintenence.
check out locally owned gyms getting rid of equipment, used equipment stores, and the paper......rich people who dont ever use their stuff will part with it cheap if you come pick it up usually.
also...you may be able to lease one fairly cheap....that is always a good option since you may get tired of it and want to switch to an elliptical or something later..plus your investment will be minimal in case it just turns into an expensive clothes hanger like mine did....and so did my treadmill ($2500)....now I just go to the gym and that seems to work better for me...lol.