Check out the Hawaii Entertainment Book at
http://www.entertainment.com/index.c...ate=&book_zip=
Then check out these two threads that tell you how to get an Entertainment Book for $5.00 total
http://www.flyertalk.com/forum/Forum...ML/001584.html
http://www.flyertalk.com/forum/Forum...ML/006859.html
There are several threads on Oahu transportation and Hanauma Bay on the about.com Hawaii message boards at
http://forums.about.com/ab-hawaii/start/?lgnF=y
although it is the most frustrating board to navigate and find stuff that I've ever used. Once you find a promising thread, though, there are often lots of locals posting with good info.