Competitions, Records, and General Stats

WCA - Official World Cube Association site

Speedcubing - The Original Stats Page

Speedcubing Forums 

Speedsolving - General (Biggest) Forum

Twisty Puzzles - Puzzle Builders/Collectors

WCA - Official World Cube Association Discussion

Yahoo - The Original Forum (old-school!)

Hardware

Speedcubes - Stefan's comprehensive site.