There is so much people can say to help you, just search the postings and you will find all the information you need.
Basically, get some leaflets/cards printed offering your window cleaning services.
I personally prefer door to door canvassing, I find the results are better.
I would just say to people at the door that you are expanding into the area and wondered if they needed a window cleaner?
If they already have one just leave your card incase they ever get let down, otherwise try to sign them up.
Pricing will depend on your area but set yourself an hourly rate and charge against that. Most window cleaners work around £25 per hour.
If you need specific advice just post on here and I am sure everyone will help you out.
Best of luck,
Trev