You can be a volunteer editor right now! As this directory's goal is to be the most open directory possible, anyone can edit any entry at any time - just click the "edit" tab at the top of the page. You don't need to know HTML, or create a log-in. There is some simple wiki markup that is helpful to know, but is also not necessary.
Please do take a look around and read the help documents, but then be bold in your edits - don't be afraid. In particular, please feel free to expand on entry descriptions, to categorize pages that need it, and to edit pages that sound like they contain a lot of marketing verbiage.