- Science Fiction and Fantasy Writers of America, Inc. (SFWA) — THE (mostly) professional organization for SF/F writers.
- Science Fiction Poetry Association (SFPA) — for speculative poets of all stripes.
- International Association of Media Tie-In Writers (IAMTW) — because “work for hire” doesn’t mean “phone it in.”
- Sisters in Crime (SinC) — for women who write crime, not commit it (generally speaking).
- Ralan.com — one of the best on-line market listings for SF/F/H markets.
- Duotrope’s Digest — the other one.
- Absolute Write — great place to find info and waste time you should be spending writing.