Being on the other side of the fence, as a "frequent buyer" I can tell you that most owners have no idea what their TS is worth. They think it is $10,000 when in reality it can be found for $200 on eBay. Not that eBay prices are what you should sell it for, but I would watch some eBay auctions closely (after they close because prices change a lot in the last 10 seconds) just as a gauge. Then perhaps price it a little above that if you truly want to sell it. You should list them with online places like Redweek.com and myresortnetwork. And anticipate a good year for the process. If you need to sell it faster, your only hope is eBay unfortunately.
FYI, unless your TS is incredible, amazing, very popular and has a big name attached to it (Marriott, Westin), I would not plan on getting more than a $1000 for it. If it is a low demand week (Silver season, etc), I think you will be lucky to give it away for a $1 plus closing costs.
Prices are really, really low right now and if you can at all try to rent it for 2009 and not sell till later, you will be much better off.
Katherine