TUG is the Timeshare Users Group. It is a great source of information about timeshares in general and has a useful ratings system for many timeshare resorts.
You can find it at <a href="http://www.tug2.net/">www.tug2.net</a>.
Another similar resource is <a href="http://www.timesharingtoday.com">Timesharing Today</a> - which has both a website and a monthly magazine.