Has anyone stayed in a hotel in Montmartre that they liked and was a decent price?
Presuming you mean the Montmartre area of Paris, I can recommend the Hotel Caravelle (3 star) on rue des Martyrs in the 9th arrond. It is just a few steps down the road from Montmartre. We took refuge there from a terrible apartment we had rented and it was very satisfactory and is in a very arty neighbourhood with lots of restos & neat shops.
I just got back tonight from Hotel Regyn's Montmarte and it's the first hotel in Paris I feel like I can actually recommend. It's not luxurious, but it's fair for the price point and we were able to get a room with a view of the whole city including the Eiffel tower for no extra cost. There is an elevator although if you stay on the top floor you still have one small flight of stairs. Rooms aren't huge but they're not smaller than a typical Paris room, decor is nice, if slightly worn. Note that the rooms with a view are also loud if you want fresh air. Doubles are 122 though, which is a fair price. The area around it is great for eating and drinking. That said, I don't know if I'd stay in Montmarte again, it's too inconvenient to everything else I wanted to see. If the focus of your trip is Montmarte, great, otherwise, I'd stay somewhere a bit more central or at least on a better Metro line (the 12 guarantees you have to transfer at least once to get anywhere, plus there's 90 steps at the Abbesses station!!)