There's also the following:
Weller's in Kailua. No wargames, but they have a small selection of model kits, hobby tools and Tamiya paints.
Hobbietat in Kaimuki. No wargames, but lot's of building supplies like wood, plastic, glues, paints etc...
Hobby Company in Aiea. No wargames but they are a hobby shop.
Jelly's in Aiea. Small selection of GW and board games.