We should have a simple form for users to submit an item to the directory from the directory page, ideally with a one-click approval process to prevent spam, duplicates, misspellings, etc.
This would lower the barrier to entry (currently people are asked to visit the "connect with us" page) and make it more likely that the directory will stay updated.
This would be a simple issue for a full-featured CMS, but I'm sure we can come up with something.