There's a lot of good advice on this thread. I never approach family or friends with business opportunity's. I'd say the best approach is not to approach at all but to simply get others excited about what you are doing without presenting an opportunity to them at all. Get them asking questions and then say something like, "If you know anyone who may be looking to get involved let me know". If they are interested they most certainly will let you know. If you are dealing with a business relationship things can be a little more forward of course.
A great way to get cheap private money is using seller financing with a substitution of collateral clause so you can move the financing that is in place from deal to deal. There are several investors doing this very successfully in my area.
Also, I'm sure that you have heard of a "Credibility Kit". I would put together a nice leather portfolio with your resume, credit report, several deal case study's showing details of the transactions and what they could have made had they funded the deal, testimonials of any other lenders you have worked with, as well as home owners. You could also insert some content about cash flow, risk...ect