Find a meetup group (http://www.meetup.com) in your area. I did this a couple of years ago and made tons of new friends and brought myself out of my comfort zone.

I've met such a diverse group of people over the years that small talk has become much easier. This was always a problem for me in the past. I'm much more relaxed now when confronted with situations where I have to interact with people I don't know.

Like anything, it's just going to take practice. You can't read it in a book. You just need to go out there and do it.