The National Space Society's Downlink #85 broadcast email has some prize-related news I've covered before (Google Lunar X PRIZE team announcement, NSS Space Elevator Team), but it also has a new prize article. This one is on the 'Return to Luna' Short Story Contest. Among other prizes, the winners will be in a Science Fiction print anthology called 'Return to Luna'. They're looking for a certain flavor of story you might expect the National Space Society to prefer; see the link for more details. Judges include some well-known space-oriented Science Fiction authors. Here's more on the publisher.
Spaceref and Space for All also are helping get the word out on the contest.
Also, although I can't find any confirmation of it on the NSS site (so make some phone calls before writing that story!), the site linked ahead states that the NSS is also still part of the 2nd Annual Jim Baen Memorial Writing Contest.