You can't really have anything appraised online. You can find appraisers in your area by using the internet.
However having antiques, one-of-a-kind pieces, and other valuables I wouldn't trust an appraisal from a picture alone, and would want to have the person appraise it in front of me just in case of any damage or negligence during an appraisal.
You might want to check out the Antiques Road Show on PBS.com or see if there are antique shows in your area. You can always find buyers and interested parties and appraisers at those places.
Also always do some of your own homework on similar items values. I never take an appraisers price at their word. Think of it like a flea market, they want to buy it for a lower price, you want to sell it at the best price.