And it's funny because I just read a blog post by someone I follow http://teaandbiscuits42.blogspot.com/2011/08/wip-madness.html who has also started a new WIP. She asks some good questions at the end of her blog which boils down to "How do you feel when starting a new WIP?"
I, unlike the original poster, don't feel nervous. I spent a year and a half living in Midswich Maine with all the residents of my fictional town, and as much ad I love them I am happy to take a break. There is a Buddhist saying which goes something like this, "Everyone is special, but no one is especially special."
A lot of authors seem to get very attached to a particular caste but I don't. I certainly like everyone in Tea Times Three, enough that I have two more books planned, but I also have a lot of other ideas with lots of other characters, some planned, and some I'm just making up ad I go.
The new WIP I plunged into, head first when a couple ideas I've had in the back of my mind collided and an idea sprang forth. I started writing without even the main character's names in place. Heck, her personality wasn't even formed yet. But I'm learning all about her as I write and I've honed her personality. I have a few things to change at the beginning, but the book, the world, and the characters are taking shape as I go. I mean the main character's name has changed three times!!
To me that's the only way to get to know a story. Write it. The characters will surprise and delight you! If you have a book or a an unfinished work by the end it doesn't matter, you've still learned, and practiced and written something. And by sheer practice the next work will be better still.
I do worry at times I'm waisting m,y time. I worry I won't finish. I worry my ideas are dumb. BUT I don't let it stop me. Every new book gets off to a joyous and exciting start! Whether it stays that way seems to be my biggest hurdle. The inevitable mid-book blues set in. I get stuck, I start to worry. I start to doubt. THAT'S when In start to freak. Not at the beginning. I hit the ground running, then slow, then trip, then pick myself up THEN hopefully, stagger across the finish line, only to have to rewrite and edit.