Just a few I can think of from the top of my head:
FutureProducers.com (Obviously lol)
Audio.tutsplus.com
Beattips.com
HipHopMakers.com
Reddit.com
The last one may seem weird but if you give it a chance it's actually really cool and informative. They have a few sub-reddits (Sub Forums I guess?) that are great such as EDMProduction, MakingHipHop, AudioEngineers, WeAreMusicMakers and Logic_Pro. The information and conversations provided there are great and I can kill plenty of time on there while in school or interning haha.