http://community.livejournal.com/twoseekers/
The first Harry Potter livejournal community for Cedric/Harry fans.

http://community.livejournal.com/harry_and_ron/
A writing/artwork/discussion livejournal community based on the idea of Harry Potter and Ron Weasley (characters of JK Rowling's amazing Harry Potter books and movies) being more than just friends.

http://www.walkingtheplank.org/
The home of all your Snape/Harry needs. Here you will find quality fanfiction, wonderful art, meta, and forums to discuss our favourite ship in the Harry Potter universe.

http://community.livejournal.com/hg_slash/
A livejournal community dedicated to the slash relationship between Ginny and Hermione.

http://community.livejournal.com/fleurhermione/
A livejournal community dedicated to the relationship between Hermione and Fleur. Members only.

http://community.livejournal.com/harryslash/
A community dedicated to slash that involves Harry Potter from JK Rowling's Harry Potter books. The slash can be with Draco Malfoy, Seamus Finnigan, Ron Weasley, Neville Longbottom, or any other male character you can think of.

http://www.bewitchedmind.net/
Snape site. Quality forums and archives. A place for intelligent discussions, reading and fun.

http://community.livejournal.com/harrylovesdraco/
A livejournal community for all the Harry Potter/Draco Malfoy shippers. Fanfiction links for H/D is always welcome.

http://community.livejournal.com/hpslash/
HPSlash is an open livejournal community for fans of Harry Potter slash, where all couples supported!