Vst4free has tons of VST(i)s in their library, and with a brief description and star rating on each sound or program you shoud be able to find what you like.
Vst Planet gives you information and updates about new VST(i)s and updates about them.
MyVST showcases free VST instruments and effects. Updated frequently on their YouTube channel.
14000 free Synth1 presets! from the "Very Random Streams". This zipfile gives you 14000+! Synth1 instruments, and instructions on how to install externall banks.