Heed the words of veinglory.
You haven't even mentioned the title of your book to people you are talking about it to.
Put a link to your book in your sig on all forums, in your email messages. Print up cards and leave them around bulletin boards in the "real" world. Display your book title and URL prominently on your notebook or gym bag, your T-shirtm your coffee mug at work, a button pinned to your jacket or hat.
(
Cafe Press is a big help with that)
Put a sign on the doors of your car, a sign in your front yard. Donate a CD version of the book to raffles and charity auctions.
Etc.
Obviously there is a personal line you will draw there, but the important thing is to realize that you're now in the business of promoting your book, and yourself. There is absolutely no benefit to being shy. You will probably find that people ask you about your book when they see such displays. They will think it's cool to be talking to a writer, not that you're a geek for displaying evidence of that. Then you hand them a card with your URL on it.
You can get cards for free from
VistaPrint by the way.
You have a book out. Be proud. Let it be known. ASSUME that it's something people will want to read and enjoy if they only knew about it.
