SuperCollider class libraries and plugin downloads by blackrain and Joshua Parmenter are now hosted by SourceForge. UGens are available here for Mac OS X (pre-Tiger and Universal Binaries) as well as scripts for building on Linux.

Builds of SuperCollider with pre-installed extension libraries are hosted here.

The old realizedsound.net download page is here where there are still a few downloads not hosted at either of the above sites, as well as some older versions of the class libraries listed above.

Any problems or questions? Contact josh at realizedsound dot net.