I've been on the radio with Harold Lacy, who wrote a book on this you can buy at Amazon.com. The audio of some of his radio programs may still be available at www.jbsba.com. Basically what he says is start asking everybody you know not whether they would be interested -- because that's awkward -- but rather who they know who might be interested. Eventually you'll start to find some names.
Don't forget a web search, there are groups of Angel investors, but don't bother doing a mass mailing or anything because you won't get anywhere with people who don't already know the restaurant business or bar business. Check out what they do before they contact them.
And remember to see the whole thing from their point of view. You want them to spend money. Always keep at the top of your mind how they are going to make money.