can not find WMA files in iTunes, for borrowing library books with Overdrive Media Console

I have borrowed audiobooks from the library, using iTunes and Overdrive Media Console for years. some months ago, I was suddenly unable to. thought it was my old computer, so bought a new one. took weeks to be able to get an upgrade from Windows, and when I was finally able to thought my troubles were over.

but, no, now the Overdrive Media says it can not connect to iTunes. someone at Overdrive said iTunes had to be the default player for WMA files, but I can not figure out how to make that happen, since there is nothing that looks like 'WMA files' anywhere on my computer. any advice? I can't afford to purchase audiobooks, and I really miss being able to borrow from the library. this new computer has Windows 8 OS