Additional questions: Are you looking for demos, or a complete package including boots? Are you looking to rent with the goal of trying out new stuff before buying or just to rent to have gear to ski on?
My son demo'ed from Vail Ski Tech, in Lionshead Circle last year. Reasonable prices, good service, seemed to have a good selection. We got a discount coupon, too. My wife rented from Charter Sports in the Marriot at Lionshead- limited selection, less than great attention and help with boot fit, but cheap (special deal since I was at a meeting and staying there). Kenny's Double Diamond has a great selection, knowledgeable staff, relatively pricey. Vail Sports has locations all over Vail village, but I have no experience with them, so I can't offer any comments.
The advantage of renting in the village is obvious- the ability to trade in for something else, get problems corrected on site. Steve's implied suggestion of renting in Denver or on the way up will be cheaper (maybe by a lot), but could be a problem if you have problems with your gear on the hill. I would be reluctant to go this route if you are renting boots, too.