Asmokindeal's advice is solid. Here are some quick additional thoughts:
If you really have anxiety that is stopping you from getting conversations going then for now I want you to become more social in general. If you were to say hi to a grandma, or ask a guy in line a question would you feel the same, or any, anxiety? Basically is this just happening when you want to talk to women that you are attracted to?
If so then let's take "The Outcome" out of the picture for now. By that I mean consider adopting a new way of thinking. I bet that right before you start to feel AA that some thoughts pop into your hear, and you have a conversation with yourself. Think about that right now. Just stop and image for a moment that you are somewhere and you see a girl that you are attracted to. Now, looking out of your own eyes.. looking at the girl.. what is the first thing you think about? Are you able to do that?
Let's continue.. what is the next thing you think.. how do these thoughts affect the way you feel. What emotions do you feel and how do you notice them changing with each thought?
Taking a moment to go through this process is vitally important to working through what is underlying your approach anxiety. If you have difficulty imagining this then it will most likely have an even bigger impact on freeing your social self.. once you recognise these thoughts and associated emotions.
Make sense?
For example I worked with a guy in San Francisco in a group setting. He had created a routine stack, and was practising it with the group. What struck me immediately was that he was being insulting to the girl. He was supposed to have written down teasing flirtatious statements, to help create chemistry. He was instead practising being an asshole. Using a routine stack can be a good learning tool, but eventually I think it is best to drop the routines, and/or routine stack, in favour of being more natural and genuine.
I asked him the same questions.. He imagined seeing an attractive girl. He pictured a scene where there was a small group of people, and in that group was a girl he found attractive. In his mind the first thing he though was "wow. she's hot" that made him feel desire basically.. the very next thing he though was "she's going to be a bitch to me."
Bingo! Right at that moment he was tainting ALL of his interactions with women. His belief that women were always going to be bitchy, made him rehearse being an asshole. Had he gone up to any girl.. he had pre-planned responses to things she would not necessarily had said. The very fact that he would have said those things would have made any woman react as a total bitch.
I told him what I personally thought, and we worked through replacing his beliefs with new thoughts that would prove to serve him better. He re-wrote his flirtatious teasing statements, and then ran through his routine stack again. It was a night and day difference. This time he was flirting.
I hope you can see how this process of understanding where your emotions are coming from will help you.
Other things come into play, such as; building memories of positive reinforcement, and mental rehearsal or meditation.
From what you wrote Ditto I would start with this exercise. You can do this exercise for any situation. Public speaking, or talking with anyone!
Then definitely go out and start developing your Social Self by talking with people everywhere. Use your wit.. develop your sense of humour, think of ways to put a smile on peoples faces. the more social interactions you have the better you will become at getting a sense for where people are emotionally at, and what they are thinking in response to things.
Good luck and let us know how you get on. If you are interested in some coaching then send me a PM, or use the website contact form.
Cheers.. J!