At expertsatellite.com I just ordered a 2 room 2 tivo + 3lnb dish system for $169. Let me know (or actually don't, I got a *pretty* good deal I think) how I did. Basically, it was $69 for a tivo + 2 lnb + receiver, but another $100 for an extra tivo.
I'm currently a dishnetwork customer on the digital home plan with a PVR508 and a Dish301 receiver, and am getting the sense that if I ever want to upgrade to anything in the future with DishNetwork, no matter what, it will cost a bit of money. I think DirecTV is a little more competitive. Anyway, I hear DirecTivo kicks PVR508's a**.