Not at all! As a matter of fact I am a newbie to upgrading computer components (just started last week) and I recently purchased a fully modular power supply (CX750M) and it was a cakewalk to hook it up to my components. The process is about as easy as plugging in cables and with a fully modular PSU, you have the option of choosing what cables you need and want to use.
I hooked up my brand-new PSU just two days ago and it was MUCH easier than I thought. You have nothing to worry about!