Have a look on ebay and see what other Tenere's of same year of manufacturer, and similar mileage go for (*), that way you can get an idea of how much to fish for, once you've done that, advertize it in Bike Trader, MCN and any other bike mag, stick it on eBay at an auction, not buy it now, start with a very low price, like �50 but make sure you set a reserve price which should be that average figure they go for on ebay (*) and add a little more to cover the extra ebay/paypal fees that they will deduct because of the reserve price.

Good luck