We have flown to Hawaii 3 times over the past six years in June/July from the East Coast. We live in Virginia and can fly from 5 different airports (RIC, ORF, DCA, IAD, BWI) pretty easily. I always check all 5 to get the best deal.
June 2009: Flew from DCA to Maui, traveled on Thursdays, bought tickets in early May for $420 r/t.
July 2011: Flew from RIC to Maui, traveled on Friday and Tuesday, bought tickets in early May for $750 r/t.
June 2013: Needed multi city tickets so we could stay a few days each at
Disneyland, on Kauai and on Oahu. Flew from BWI to LAX, LAX to Kauai, Kauai to Oahu, Oahu to BWI. I found tickets for $850 in mid February, but didn't buy then because previously we'd always seen the lowest prices in early May. I was sure they would drop in price. Nope! They just went up, up, up. We paid $1100 per ticket. Totally blew my vacation budget!
Good luck with your flights. If you find something good, jump on it. I checked the Kayak.com website daily. They have a special tab to search for multi city tickets.