Here's a list of suggestions for offline promotion for your web site:
Put your URL on the back window of your vehicle (as long as it's easy to remember)
Get stickers and put your url on every piece of mail you send out. For that matter get envelopes printed and put your url on them.
Post flyers or business cards on community bulletin boards in your town.
Send an email to your friends telling them about your new web venture. Don't spam them, just send a nice email letting them know what you're doing.
You can advertise in the yellow pages for your business but the effectiveness of yellow pages is dwindling. If you do choose to use the yellow pages, by all means put in your url.
Other places to put your url are below:
business cards
letterheads
envelopes
checks
invoices
receipts
address labels
fax cover sheets