Noticing Newbies

I think this is my first post. I have been planning to write a book for a llllong time. I don't know where to start. I have a file I have been throwing stuff in for ages. I have writing ability, or so I was told in high school, at poetry reads, and by others. I am paranoid and neurotic about where and how to start! I get excited about writing but tighten up like a pig on fly day when I get to the pen.
Maybe I need an experienced successful writer to hang around with. I should start 'Writing 101'. I even get worried that I might lose my creativity if I study too much technical and how to stuff. It's time to buck up, or burn the bologna.