I get all kinds of adaptors for fans from www.microcenter.com
They give the brand names of them so you can look them up elsewere. I have a 2 pin to 4 pin molex adaptor than cost like 3 bucks american.
I didn't see them either and xioxide listed them but had no info on them. Micro center has them on the wall but I guess it's not a big demand item so not on the website.
Print this off and use it to find the correct adaptor. This adapts the 120mm from my old psu.