Hawaiian Air is currently running a promotion to HNL from various portals on the west coast for $334. Fares must be booked by 5/5/11 for travel 9/6-11/17/11. Some example fares are shown below.
The nice thing I like about the Hawaiian Airline site when searching fares is how easy it is to scan rates flexibly on a weekly or monthly basis. For example, the following two screen shots were taken running a sample itinerary in September of this year from LAS to HNL.
The total cost RT works out to $355.80 per person after taxes and fees. Overall it is a pretty reasonable rate for the west coast.