Just do some google and youtube, its the most simple thing you can learn(no offense), heck why not even just open up the Pc you got right now and get to know he components and remove them / play around?
First learn what the connectors and cables are
Get the mobo out, install the CPU and heatsink, install it on the case...then connect the AUX 4 pin / 8 pin power cable then connect the 20/24 pin ATX connector.. connect the Sata cabels to your HDD and then connect the molex / power cables to the HDD.. install the ram, install the graphics cards and dont forge to install the fans ...
just a few cables...cant get any simpler
or you know what? take all the components to a local Pc shop and pay the guy 10 / 20 bucks to give you a hand, or just call a friend who know a bit more then you do