This article is from the Science Fiction Fandom FAQ, by Vicki Rosenzweig vr@panix.com with numerous contributions by others.
You join by sending money for your membership to any active
Worldcon committee. Worldcon sites are chosen three years in advance,
by a vote of members of the then-current Worldcon. Thus, in October
2001, there are active committees for 2002, 2003, and 2004, all of
which will be happy to sell you a membership. The Web site
http://www.worldcon.org/ is an online home for all Worldcons. You can
buy a supporting membership--which entitles you to nominate and vote
for the Hugo Awards, vote for the site of the three-years-later
Worldcon (for an additional fee, which gets you a supporting membership
in that future Worldcon), and receive all publications--or an attending
membership, which gets you all of that plus the chance to attend the
convention. The price for attending memberships increases as the
convention draws closer. (Getting money early is useful for a variety
of reasons--the con has expenses well before people show up for a
five-day extravaganza--and knowing how many people will show up is
useful to people who are trying to plan everything from how many panels
to have on Friday afternoon to whether a particular hall is big enough
for a convention banquet.)
 
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