I'm not sure if this is a well-known site, but it amused me for a few minutes. http://www.thesmokinggun.com/backstagetour/index.html It lists the backstage riders of 100-odd musical acts. You'd be amazed what some people ask for!
It's fairly well known but still worth mentioning. They have some great stuff there... all the stars who want bottled water but it can't be Evian or they'll freak out. They want their dressing room to look like home, and an assortment of everything in the grocery store (maybe they'll eat one of the many things set out for them). Of course, as long as the backup band, dancers, etc. have a catered dinner, drinks, and a place to crash, they're expected to be satisfied, like normal people. It also explains the Caliwussification of the Chili Peppers. I mean, a meditation room? Aroma candles? No wonder these guys don't rock very hard anymore.