Price guide, http://www.antiquecast.com , allows searches of recent auction results. Super search lists sale items at several auction sites. Pictures are often available. Although this site is pitched towards antiques and collectables anything auctioned can be searched. Concise searches are best with the 3 most characteristic terms. For ready reference this site is worth bookmarking.

The search didn't seem to have heard of any of my favourite military watches and came up zero when I know of some currently on ebay. Strange (but true).