Looks like Hugh McLaughlin. As for ID there is no one site to check. Lots of nurseries have photos of rexes they offer. I would do an image search in your favorite browser for rex begonia and hope you find something that matches your mystery plant. Some begonias are pass along plants and have no name or the name has long been forgotten. The big box stores often sell begonias as rex begonias and they may not even be a rex.