Discovered this one recently. Does anyone know about its origins? Could it work as a given name? It would be strictly middle name material for me if I were to consider it.
Not sure about the origins. I think it could work as a MN, maybe even an FN with the NN [name]Noa[/name] 
Maranoa intrigues me. At first I thought it might be from the Hebrew names [name]Mara[/name] (which is what [name]Naomi[/name] wanted to be called when she returned to [name]Israel[/name] after her husband and sons died, which means “bitter”) and [name]Noa[/name], but when I googled it, I got no name hits… Apparently it’s a region in Queensland, Australia, and The Wiggles also have a lullaby song they produced called “Maranoa Lullaby”… It might be a Maori name, but I couldn’t find anything on that, either.
I found a few sites that referenced Maranoa as a surname. The site (http://www.boroondara.vic.gov.au/our-city/history/ward-names) explained that Maranoa as a surname derived from native Australian plants named by [name]John[/name] Middleton [name]Watson[/name]–he named the plants after a river called Maranoa. The site says that Maranoa comes from native (I’m guessing Maori?) words meaning flowing, alive, or running.
It intrigues me, and I like it, the more I think about it, but I’m not sure I would use it, personally. It might make an interesting, cool MN to a short-and-sweet one-syllable name ([name]Eve[/name] Maranoa, [name]Claire[/name] Maranoa, [name]Fleur[/name] Maranoa, [name]Wren[/name] Maranoa, [name]Kate[/name] Maranoa, etc.).