I had been looking for PPG suppliers onlne, but have not run across any. I have a local supplier that I used for a truck rebuild a few years back, and will go with them if nothing else pops up. Mills supply has rust repair panels.
Ditto on Mills supply - good quality, good deal - got 2 sets of quarter pannels for 2 of my VX for ~150.
For paint - went to my local brick and mortar - paid $50 for a pint of base and activator, clear will be $50 extra. I think I'm done with that place, next time I'll just get a gallon of single stage for $35 from this guys: http://www.paintforcars.com/ and spray the whole car.
Not much choice locally for auto paint, but Home Depot said they'll color match alkyd enamel, and so will the hardware store - theirs only $10 a quart.