Alternatives?
You can simply use mail forms and a formmail script from a site such as Matt's Script Archive to read the forms from your cgi-bin directory using a script such as formmail.pl. Few personal sites allow the user cgi-bin access, but most commercial web-hosting facilities permit it. If you have a commercial site, except on a page of links to individual e-mail recipients, better go cgi than use the encoder. Explaining how the script works in detail and how to set it up is outside the scope of this article. I don't regard a full formmail setup as being worth the trouble for a personal site that's likely to be viewed by only a handful of people.
Alternative software packages and other solutions for alphanumeric mailto: encoding include the following:
Web-based: Advanced Email Link Generator with Anti-Spam Encoder (there are many others) for mailto generation based on form entries entered by hand on the page.
Windows, Linux, MacIntosh: Nothing found at Tucows or via a brief Google search. If you aren't using Windows, for a lot of pages, you should get access to a Windows box and install and run NATATA. It's faster than doing this manually via HTML table or via third-party webform, even including dial-up download time.
Some web page authoring tools might exist that support the automatic creation of this kind of encoded mailto: hyperlink via menu for software configuration. If yours does this, you don't need the utility.