Most of the big businesses attach business cards or fliers with out going mail. This works for companies who send bills to their customers. For those who have customers paying online, they can send the information through emails.
Advertisements can be done, in the locality, by placing fliers on the bulletin boards of the local grocery stores, businesses, barbers, or butchers. People frequent these places and there is a possibility of getting a good response. Some businesses place a jar at the reception counter where the business cards can be dropped for future reference, while visiting them.