You shouldn't be too worried about the ones your missing. You are missing 14 states, but 11 of those haven't come out yet. And North Dakota came out August 28th, so it's not that surprising that you haven't seen one yet.
Michigan and West Virginia are the only two that have been out for awhile that you're missing. You can see the schedule for the remaining states here:
State Quarter Schedule
Unfortunately, your collection project will take until the end of 2008 or into 2009 before you're able to snag a Hawaii.