Typically, people will either post the information on the cruise meet thread for the organizer to add to the list. Or you can use the conversation option (what PMs are called here). This option is really nice as there can be up to 20 participants in a conversation at a time. That way, the organizer doesn't have to repetitively post information to individual people. The kink in this plan is that everyone participating in the conversion (hopefully all those who are on the FE list) must have at least 10 posts to do so. An easy fix for this is for those who need to up their post count is to head over to the Test Board and post there.
http://www.disboards.com/forums/test-board.88/
Another option would gathering individual email addresses, but posting those on the cruise meet thread isn't encouraged.
Here's a little guideline I set up for FE organization, hope you find it helpful:
Setting up FE group
There's really no "rules" as to how a FE program runs. Basically someone maintains the list of those who wish to participate. The group can decide on what information is necessary to produce FE gifts. A basic list may only have DISname/room number/number of people in the room. A more involved list could be first & last names/ages/room number/favorite character/favorite color/allergies/whatever is deemed necessary to know. Also a decision can be made as to size of FE. Some groups break out the list(s) at 10-15 rooms max, so that there are multiple lists (and some people will participate in more than one list). Other groups just make one big list (upwards of 20-30 rooms).
At some point the list will "close". Typically this happens 30-45 days out from the cruise, so that everyone participating has time to organize/prepare their gifts. Shortly before this time (about 2-3 weeks prior) the organizer will either post the list (usually via a conversation is best, as that's more private), or directly on the Cruise Meet thread, to confirm everyone on it is still participating. It’s important to make a statement about
"anyone not confirming by XX date will be dropped" at this time. A little harsh, yes, but often there are people who will post on the cruise meet thread as soon as the reserve the cruise and say “I want to participate”, and are never heard from again.
Once the list closes, the organizer will post the final list. Also, a decision must be made as to whether to allow late additions. Sometimes there is a "pixie dust" list. That is, basically, a latecomers list that gets posted about a week out from the cruise that others may or may not add to their "final" list. Be sure the "pixie dust" list participants realize they may or may not get gifts from others.
The other "biggie" is no other social media sites are allowed to be linked or search directions posted as to how find that other site here on DISboards.