http://www.kvr-vst.com

Here comes a must-see site for every VST enthusiast! This is probably the best
available resource concerning VST instruments and effects. You find all your plugin
heart desires here: All (!) available VSTi with their specs + (exclusive) soundbanks
and patches + reviews + latest news + a great forum + ratings + tutorials + links + ...
If you are only slightly interested in what is going on in the VST world, surf over to
K-V-R, and I suggest doing that daily, as it is usually updated that often!
 

http://www.discoverysound.com

This is a Japan-based company that has released many ethnic/world sample
libraries, including two excellent libraries with Japanese samples ("Spirits from Ainu"
and "Okinawan Tradition").
 

http://www.plogue.com

Plogue are some cool developers from Montreal/Canada. They have two strange but
beautiful freeware plugins for download (Mac/PC) and also Plogue Bidule, certainly one of the best (modular!) VST hosts out there.
 

http://www.bluelife-media.com/audiolinks/

This site has a collection of over 500 quality-proofed links to audio articles from all
over the net. No matter if beginner, advanced user or professional, everyone can
find some useful information here. The database is fast, searchable and allows you
to add new links (all submitted links are reviewed before being posted).
 

http://www.camelaudio.com

Camel Audio is the creator of innovative audio plugins. Cameleon 5000, their latest
plugin, is an additive synthesizer with powerful morphing and resynthesis abilities.
Definitely worth checking out!
 

http://www.refx.net

This is the home of reFX, certainly one of the best VST companies out there. For very
reasonable prices you can get some real killer synths that you won't find elsewhere!
Highly recommended!
 

http://www.flstudio.com

FLStudio is by far one of the best and most affordable VSTi & DXi host available.
It includes its excellent own generators and samplers, but the wide range of plugin
and synth standard it supports makes it a real universal all-in-one solution for
creative musicians.
 

http://www.audiocourses.com

AudioCourses is the world's largest Distance Learning Audio Recording School for
Sound Engineering & Music Production.
 

http://www.dontcrack.com

The ultimate Audio Freeware resource for Mac and PC! DontCrac[k] hosts a community
of passionate audio software developers who collaborate with final users in order to
offer them the best audio products.
 

http://www.bteaudio.com

The BTE Audio web site features articles, reference hardware designs and software utilities for the audio enthusiast.
 

http://www.traxmusic.org

"A frequently updated site, dedicated to bringing you the best and latest news in the
world of Pro Audio and the Computer Music scene on the Net."
I might add that you find some exclusive reviews and especially interviews with VST
developers on this site that are really fun to read! 
 

http://www.em411.com

A great place for all those interested in electronic music! You can find a healthy mix of
audio software related news, an active userbase of experienced musicians, many
program reviews and a helpful community here! Registration is free and I doubt you'll
regret going there :-) 
 

http://www.londonschoolofsound.co.uk

The London School of Sound provides a wide range of courses from DJ to music
production, with an emphasis on intensive, advanced courses. The web site also
features articles, reviews, and a forum with lots of information for music enthusiasts.
 

http://www.theoreticalplayground.co.uk/forum/index.php

A new forum for discussion of audio programming, DSP, synthesis, algorithms,
circuit bending, production techniques and much more. Worth checking out...
 

http://www.synthzone.com

Synth Zone is an attempt to ease the search for synth resources on the Internet.
You can find dozens of links specially for your favorite hardware synth: manuals,
infos, editor programs, soundbanks, patches, and so on.

But also the audio software links is pretty well equipped, so if you are new to the
world of "computer" audio, you can take a close look and rummage in the various
categories for hours!
 

http://www.stelkens.de

This is the homepage of Joerg Stelkens, creator of the mighty Crusher-X granular
synthesis system! Some other very interesting projects can be found on this page
as well.
 

http://www.webmassiva.com

Jorgen Aase runs this site and has some wonderful stuff to offer that deserves
mentioning: Massiva (a great sequencer/VST host), Cyber (a virtual sampler),
Synthetic (a synthesizer) and especially Energy XT (a modular VST plugin/host)
Don't miss checking out his great stuff!
 

http://technoforum.de

Technoforum.de is the first German-based community for electronic music.
The forum is in German language only, but don't hesitate to participate in
English, most of the users are willing and able to communicate in English as well.
There is a lot of valuable information to be found there!