Tournament golf in Arizona is everywhere and at every level. A great place to start is-

The Junior Golf Association of Arizona
 
 
There are other tours for more advanced players some of which require performance based entry to be able to play. American Junior Golf Association is the highest level a junior golfer can play. They have some entry level events, events for younger players 12-15, open events that require status to play, qualifiers for those open events and Invitational events that are for the top players in the AJGA.
 
 
Other Junior Events-
 
USGA Jr. Am qualifier (refer to the JGAA website)
 
FCWT Golf
 
 
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