I had been searching for cheap airfares from LAX to KOA (Kona,HI). I did notice that American Airlines was one of the very few, if any, to offer a non-stop flight from LAX. Most airlines go thru Honolulu. Summer prices were too high. I checked the prices quite frequently until one day at the end of July, I saw the price for a roundtrip airfare drop to only $394 including tax beginning the day after Labor Day. Many seats were still available. Most dates to and from (in September) were all only $394. Get this, LAX to Honolulu was only $294 including taxes in September. Now that's a deal.
Purchased tickets in October '06 from LAX to HNL for only $260 including taxes for travel for Feb 15-20 (Presidents Day weekend). I guess it pays to book early.
The price of $394 from LAX to KOA remained pretty constant on the days I chose since I purchased the tickets back in July. Recently(3 weeks prior to the departure date), the price went up to $630; very few seats were available on both flights to and from Kona. New Update as of 9/17/07 (3 days before travel) - price is now $1,084 including all taxes.
On a side note - I always do price comparisons for airfare/hotel prices using the expedia, travelocity or cheaptickets website. I noticed that prices didn't vary too much. You may get a slight discount for packaged deals. I never book thru these websites because they charge a $10-$15 service charge in addition per person. Once I have the information for hotel/airfare prices from these websites, I go directly to the hotel/airline website.