Falls can kill, even fron heights as low as seven feet. Know what you're doing before you step out up high.
For homebuldiing, normally the only scaffolding required is something like pump jacks. You can go "low-end" and get the ones that ride on douglas fir wooden poles (two 2x4's face nailed together) or you can go "safe end" and use Aluma-poles. Pump jacks that ride on aluminum poles.
I'd recommend the latter. Aluma-poles are more expensive up front, but you can resell them when you're done. Also you can save up front by buying quality used ones.
Falls can kill.
If you want scaffolding, you can buuy it or make your own. For parts look at Kee Klamp at www.rbwagner.com
Make sure all parts you use are intended for stuctural scaffolding, and that you don't overload the lower staging by building too high.