Okina & the Islands

I was just wondering which of the islands (besides O‘ahu) take an okina. I've flipped through some of the locally produced magazines here and I can pretty much guarantee that I'm not the only one with this question. I saw the okina popping up in what seemed to be really awkward places (Mau‘i). But I can't deny that finding an answer is hard - I've tried looking up the correct spelling on the state's website, wikipedia, random google searches, etc., but so far the results have been so inconsistent! This leads me to a secondary question as well: what kind of resources would you consult in order to check the on the definitive spelling of Hawaiian words?

Honolulu Weekly: A generally pretty good job in trying » Honolulu Weekly

Honolulu Weekly: A generally pretty good job in trying » Honolulu Weekly

I read editorial piece and thought about some of our discussions in class about spelling of the Hawaiian language and the use of the ʻokina and the kahakō.

Online Hawaiian Dictionary

Those of you who have never used a Hawaiian dictionary may want to know about this site. To get the English edition, click on "English Text" at the top of your screen. If you don't know the proper orthography of the word you want to look up, select "All Dictionaries" before you do your search.

Editing Hawaiian Words

I know that for the test this coming Friday we will need to know how to correctly spell Hawaiian words. How do we write the insertion mark for a kahakou? I can see indicating the need for an 'okina the same way one would an apostrophe, but do we use a caret or just draw a line over the vowel?