Ted...tell us more about the using a contactor to energize the compressor...can you add a link or p/n. I'm gonna leave the text message to the kids....next generation.
You would need a 2 pole 30 or 40 amp contractor with a 120 volt coil depending on the breaker size feeding your compressor. Basically you would run a line from your shop lights to the coil to turn the contractor on and off. It could be mounted close to the compressor or the panel. You would just run the feed through the contractor to make and break the circuit. Its a good idea other then II'm sure it would make you jump when you turn the lights on and the beast in the corner starts up. If you need a schematic I could sketch something up.
Her is a link to a contactor
http://www.kentstore.com/c25dnf240.aspxMark
