If this helps... Its a guide how to take a PC fan and hook it up to an AC adapter for power...
I'd done this when my PS3 had no clearance, just installed them into my old school HT furniture unit, by cutting into the backing it had. Braced the fans to it.
http://www.youtube.com/watch?v=kSYKArb72nA
Its really simple, and you could probably even just grab a soldering iron too, get it sorted. I'd just advise to wrap the whole live end with electrical tape after you're done.
Warning though, as some dude pointed out in the comments: "You may want to check that the voltage of your adapter is the same as the voltage of your fan. Keep in mind this method is if you DON'T want to destroy your adapter. I would recommend stripping and soldering the wires for a more permanent application.
Best regards,
Tim Matheson".
I just assumed you wouldn't overly care about what happens to a cheap big PC fan or some old blackberry wall adapter you've had in a wire drawer somewhere.