Anyone know of a program/plug-in for Premiere CS4 that automatically syncs on-camera audio and audio recorded using an external recorder? (I will be using an EX1 & 2-3 wireless lav's and an off-cam shotgun)

Thanks

I never heard of a program or plug-in to do that automatically. I have heard numerous stories where the camera sound and external sound get out of sync, usually requiring a slight speed adjustment of the external sound to get it properly aligned with the camera sound. Probably Audition is the best tool to do that. It is a matter of trial and error with the speed adjustments.

Never heared of that either. the only one I know is pluraleyes and that works only for FCP and Vegas

Regarding speedadjustments on ext recorders, audacity is also a good option and it's free.