Building a PC nowadays isn't very difficult. I upgraded mine recently and the only thing i even needed a tool for was a phillips screw driver for the motherboard. Everything else had tabs or large enough screws to tighten with my hands.

For choosing parts and being most efficient with your build i suggest using this website: http://www.logicalincrements.com/

It can seem overwhelming at first but it really isn't. Even newegg.com where you can get some great deals has profressional quality videos on how to install each component.
Hope that helps.

Later