Re:List of VST that is compatible with Sonar Producer 8.5
I think you need to be more specific in asking your question.
State your purpose as to what you're looking to achieve with specific type of VSTs.
For example, if you're looking for a good guitar amp emulator, you've got some great products from IK multimedia (Amplitube franchise), NI of course (Guitar Rig, a version of which is already included with SONAR PE), Studio Devil, and quite a few decent sounding free ones as well.
You've got such a wide variety of instruments & effects, you have to narrow down your search.
SONAR X1c Producer; SCOPE 5; Windows 7 x64
PowerPulsar+PulsarPlus+PulsarSRB+A16 Ultra; DIGIMAX FS; MTP AV USB
Core2 Q9300+DP35DP+8GB PC6400 DDR2 DIMM+GeForce 8600 GT
MCU PRO; BCR2000; Lemur/Dexter