Your best bet is to "Google" it. Then you will get a good starting point on your requirements for your certificate and dealers in your area.
Or ask in the "local region" (I'm sure it's called something like that) here on Lawnsite. That way you might find a few people who had to go through what you're wanting to do. And if they know you're not in their city, they might help you.
2013 Ford F450 Super Duty Truck
2010 Exmark Lazer Z 60" deck
2012 ExMark 30" Riding Aerator
2011 Lawn Solution Dual Hyrdo Aerator 24"
2011 Echo(backpack blower), (hand blower), (chain saw), (hedge trimmer), (string trimmers), & (tree pruner)
Craftsman 4.0 edger
2007 Big Tex 4ft metal high side 7' x 12' Trailer
2012 PJ 7' x 16' Dump Trailer
2012 Ecolawn Applicator model 200 Compost Spreader
2012 BillyGoat Force 13 Wheeled Blower & MV650SPH Commercial Vacuum