Fill your boot (trunk if you're not in the UK) or rucksack with copies of your book and take to the streets. Knock on people's doors and tell them what a fine book you have published.
Start on your own street and tell them that you live just down the way; explain what you've done, tell them how hard it is for authors to make sales and, basically, appeal to their neighbourly spirit.
Then spiral out from your home through the streets of your neighbourhood knocking on doors as you go. Make a note of who is in and who is not and revisit (at a different time of day) houses you couldn't raise a response from. Emphasise that you are a local author - people love that stuff.
Whenever you come across a local community centre - pop in and find out when they are running meetings - and then ask if you can have a ten-minute slot to talk about your book - and make sure you take a big box of copies with you.
Oh, and don't forget your family and friends. Make sure that everyone has a copy of your book (paid for or otherwise) and they know how to get hold of you to get more copies (this applies to the people you sell to at the door too). Never underestimate the power of word-of-mouth.
Of course, for this strategy to work (especially the referrals) it will help if you have a quality piece of work. It might also help if part of the book is set in, or mentions, the local area.
And if none of this appeals - send someone else out to do the job instead. Teenagers are one of the most underutilised resources going, so find (or make) a bunch of 'em and give them a mission (and maybe even a small commission).
Good luck with your book sales and new-found wealth.