Hi joe45
I sympathize. I remember feeling this way when I was 12 (When my parents moved to a new place and I had to leave evrything behind). What I found interesting was reading books on psychology "Understanding Yourself", what makes you act the way you do. I don't remember any specific names, but there are tonnes of them out there. The key here is finding out the reasons that make you not outgoing or scared of being outgoing or not confident enough about starting up conversations with other people. For each person these reasons will differ, but in the nutshell these mostly will lead to confidence issues, doubts in ones abillities, Insecurities, pesimisitc attitude and plain inexperience. You can find a whole wealth of literature covering the above, which i think will help you understand yourself and this is where work has to begin. You have to understand exactly why you act the way you do in certain situations before you can feel confident enough to put yourself through those situations.
For me finding friends is very easy. All i need to do to find a friend is go to a pub on a friday night after work, there i will find a dozen of my co-workers (Both guys and girls). I don't do anything special, just talk about my daily routine, movies, hobbies, past, present, future aspirations and before i know it i have a new friend. It's that easy.
After learning more about yourself and finding out exactly what kind of a person you yourself are, I would recommend to put yourself into social activities to get more people's experience and people's skills. Sports, dancing classes, singing lessons, outside of work co-worker activity, anything social will give you the much needed experience to achieve what you are looking for...
Hope above helps and best of luck for the future!!!
Don't cry, don't regret and don't blame
Weak find the whip, willing find freedom
Towards the sun, carry your name
In warm hands you are given
Ask the wind for the way
Uncertainty's gone, your path will unravel
Accept all as it is and do not blame
God or the Devil
~Born to Live - Mavrik~