I have generated a url from product code like,
url : www.example.com/2555-525.png
Using wildcards in URLs is useless in most cases because
the interpretation of the part of the URL after
http://www.example.com/ is totally up to the server - so
http://www.example.com/2555-525*.png might have a meaning to the server but but propably has not
normally (exceptions like WebDAV exist) there is no way of listing ressources in a collection or existing URLs in general apart from trying them one-by-one (which is unpractical) or scraping a known site for URLs (which might be incomplete)
For finding and downloading URLs automatically you can use a Web Crawler or Spider.