There are some more at MyAviaton.net and JetPhotos.net. Hilo just isn't that popular of an airport to photograph from. The waiting area has no view of the ramp, though the Hawaiian Premier Club does (I don't know about Aloha's as I haven't been in there). I can think of a couple of places to try getting approach shots to runway 8.
However, there isn't that much traffic (mostly just the usual interisland stuff), and Hilo, averaging over 100 inches of rain per year, is often cloudy.