OEM means original equipment manufacturer. And when you buy an OEM product, it's just the product itself. No manuals or retail box. Don't worry though, because your motherboard if bought retail, should come with the necessary cables to connect your hard drive.
Depends on the specs of the fans, compared to the one I suggested. I don't think you would want to spend $15 for one fan, unless you want to of course. But I'm sure that $10 fan I suggested is well good enough for the TRUE.
If you are thinking of getting the Corsair 520HX from newegg, forget about it....because the PC Power & Cooling Silencer 610W
is cheaper at the egg, and a better quality PSU in my opinion.