» Karl Fogel:
“[...] "I'd like to get more involved in open source -- how do I find a project that will be appropriate for me?" [...]”
In my opinion, if they are currently using FLOSS programs they can pick any of the ones they use so they won't need any FLOSS directory to find the right one for them. I think they must be honest with themselves about what their skills are (not just programming) and how much they want to get involved.
The most basic thing they can probably do to help is to spread the "FLOSS word" among their family, friends and acquaintances. To me, that's beeing involved in FLOSS already. Of course, the next steps could be help translating software, giving answers/support to other people using the same software and, finally, get involved in the development of the code.