Here are a few web links to answer your question...http://www.whistlervillagesports.com/rental.htmhttp://www.whistlerblackcomb.com/rentals/price.asp
The best thing about renting from Whistlerblackcomb.com is that you can try different skis through out the day. They have several on mountain locations where you can exchange for a different pair of skis.
I demoed 4 pair of ski in one day when I was at Whistler several years ago. Of course the selection only includes a few brands, Atomic, Salomon, Rossignol but it will give you an idea of what to look for in a ski.