See some earlier discussion here.

What does your gym use?
Can you research wholesale/refurbished gym equipment in your area?

I'd love a spin bike. I have tried a few trainers and I just don't like the way the feel vs. rollers. Rollers are definitely a way to go, but admittedly rollers don't always allow me to do the workout I want - to stand and hammer, for instance, or to do a Spinerval DVD (possible, but a challenge).