EXS 24 Logic Sampler Users Group

Have a look here:
http://www.hammersound.net/

In case you're on a Mac, make sure to forget about anything with a file-ending such as "sfark" or "sfpack". Unless you're using
something such as Virtual PC or so.

Also, there's some rather mediocre instruments - but others are fine.

You may also want to check out these:
http://www.musicmall-asia.com/store_Ffreebies.html

- Sascha