There's some on the audacity website.

There's also some VST ones that may be compatible with audacity on tweakheadz (google it)

This should be in riffs and recordings.
Quote by jaggysnake
Thanks, helpful

Well, you've already got the ones from the Audacity site...

How am I supposed to know where all these secret plug-ins are?

I'm sure a search engine would be much more helpful than asking a bunch of random people. (Especially since you're asking in the Pit)