The suggested loop by the muni is actually a pretty good relatively "blue" loop: http://www.whistler.com/resources/pdf/maps/whistler_bike_trails.pdf
But it'll likely take most a couple hours to do this (or more).
Kevin26's rec's are good and is basically the first part of this loop. But when done "Gee I Like Your Pants", go back up Hooktender and Tommy Moore to get to Not Satisfied/Jonny/Grand Wazoo…
If you wanna' get out of the village and have less rider's this time of year, you can park at Alpha Lake do Lower Sproat, Piece of Cake, A La Mode, back to Lower Sproat, to Beaver Pond, Danimal North, to Whip Me Snip Me and then ride the Valley Trail back to where you started. This is probably 1.5 hours for a competent fit blue square rider depending on your pace. Maybe longer? Gorgeous views and fun riding.
Good website: http://www.3dwhistler.com/?season=summer