The Dept of Agriculture site does list approved and restricted animals - but that wasn't my point. There's no list of approved plants, only prohibited ones ... so the implication is, if they're not prohibited, you can probably bring them in as long as there's no problem with bringing in agricultural pests.
On that note, it's interesting to me that certain Acroporas and Tridacna giant clams are on the restricted list - meaning if you apply for a permit, you could potentially bring them in for personal usage. Of course, you might have to write up a multi-page application explaining your husbandry techniques to prevent wild release but it might be worth it.
HFishy - I agree with your point about the Petland Kahala though - I LOVE their display tank but sorely wish that they would bring in some of the plants and animals displayed in that tank. Interestingly enough, the Petland in Ala Moana does tend to get a wider variety of plants if you check regularly (alternanthea, bacopa, E. tenellus, etc). I haven't yet seen much at Pets Plus in terms of plants that I haven't seen elsewhere but they were my source of false SAEs so I can't complain much - I do check in with them fairly regularly as well. An interesting place to visit too on the leeward side of the island is Pets and Plants in the Waimalu Shopping Center - I think I saw some actual cherry shrimp in there a year ago when I hadn't gotten the algae shrimp bug yet. On occasion, they'll get a decent plant selection in as well (I think I need to supplement my Ludwigia - it's starting to look at little stemmy)
I haven't had the time to check out HAS. Sort of interested but it's also kind of far for me.