Directory Crawler That Works On Windows and Mac.

I need an application that works on windows and mac that has an installation wizard a start up logo and an icon, all graphics will be supplied by me. The application has to allow the user to enter a directory url they then have the option to let the application crawl only the url page pasted or the complete web directory. I also need an existing program of mine to be converted to be used on a mac, it already works on windows! The software crawls search engines for emails. Thanks, andrew