You must cite sources for the information about clubs and organizations if you did not learn it from your own experience (ie: going to a meeting, playing on a team, etc).

There are several ways to do this:

1. If you talked to someone and got information you should cite that information as a personal, unpublished interview (if you can't remember the person's name, just say "club member"). See Longmans p. 219;
2. If the person gave a little presentation, cite it as an "oral presentation" - Longmans p. 220;
3. If you got it from the group's website, see Longmans p. 220;
4. If there was a handout, I think the best way to cite that is like "memo" - see Longmans p. 220, use the name of the club as the author, then the title of the handout if there was one, then the date you picked it up;
5. If you are citing an email from or about a club or organization, that's in Longmans on p. 230;
6. If you are citing someone else's summary from the wiki, use the rules Longman gives for blogs (it doesn't tell you how to cite a wiki), see p. 224

We want to know where we might find the same information; we are not concerned at this point about exactly how you provide us with that information. Getting the citation perfect is much less important than providing one!