The best site I've found on the net for VST plugins is the KVR Database
The best thing is that you can find free plugins in all categories by using it's great search engine.
Just select the format you're looking for and choose the various options to narrow your search.
You can find VST instruments, hosts, DirectX, etc in commercail,shareware and freeware categories. Some of the freeware ones are very high quality and sound excellent.
This is is a very good site and we recommend it to anyone who hasn't discovered it yet.
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