Angel investors (not venture capital firms) are the most likely candidates to get your businesses from a piece of paper to a proof-of-concept. These angel investors typically come in four distinct groups:
Friends and Family
Friends and family investors have their distinct plusses and minuses. The plusses are these people know you the best, so they are the closest to you in determining whether or not you are backable, as first hand references. The minuses are pretty major: these are your friends and family!