Unfortunately, there is nothing you can do. Karma will get him. What he did was not right, but i'm sure it happens all of the time. Even with a poorly written non-compete, there is little you can do if he is just an employee of this other company. If there is ever a next time, make sure you have a lawyer write up the agreement and get it notorized. The verbage will have to say something about having no contact with the customers being sold to you, and that he will not give their information to anyone else. You live and you learn...
2002 Silverado 2500HD Duramax/Allison ECSB
1996 Silverado 2500 ECSB
2006 Ferris 4500Z 61" CAT Diesel
2005 Exmark 48" Turf Tracer
2005 John Deere 647 Quik Track 48"