These sources are useful as a first step in identifying biographical writing.
Because it searches the full text of many books (not all books, but many), Google Books can be a useful resource when doing biographical research related to Pacific Islanders. In most cases, Google Books does not allow you to read the text online; however, it does provide you with the title of the book and the page numbers a given name appears on -- with this information, you can then find the book in the library's online catalog, and will know what pages you're looking for once you have the book in hand.
Both the Hawaiian and Pacific Collections have a great many historic newspapers, dating from the 19th century through present. Many are in microfilm, and most have not been indexed, meaning that if you're searching for a specific event, your only option may be to go to the microfilms and begin reading papers dating from the period you're interested in. However, some have been digitized, and in these cases are searchable and readable online.
Wikipedia can be a useful first step in identifying sources of information on a specific person but: You have to confirm the accuracy of Wikipedia entries using other sources. A good Wikipedia entry will cite its sources -- follow them to the original source to ensure it is "authoritative" (meaning, something worthy of citing in your paper). A bad Wikipedia entry -- and there are many of them when it comes to Pacific Islands topics--will not include its sources. In short, use Wikipedia as a very early step to help identify sources of information, but do not cite it as a source.