Hi Paul, practice practice practice.
Talk to everybody everywhere, starting with people that are getting paid to talk to you and be nice to you (cashiers, starbucks employees, bank tellers, taxi drivers, librarians, bookstore employees, massage therapists, nail salon employees, etc) do this a couple times a day and slowly but surely your anxiety will dissipate.
You also might want to try New Behavior Generator, or better yet, use a real talkative buddy as a model and use Instantaneous Personal Magnetism.
I would also strongly recommend "How to Win Friends and Influence People" by Dale Carnegie, as it gives great tips on how and what to talk about so people will like you.
George
