Collect emails in any way possible, even if its bits of paper where customers put their email on a line - you need 'bait' such as emailing out special offers but thats part of getting the customers back in quicker.
Word of mouth is great, most companies take a long time to get that far and have to spend loads on advertising - what you want to do is anything you can to amplify that.
They need to stick their neck out, be bold and add some sort of value or service that no-one else is doing.
What kind of business is it? Is it catering?
If its catering, recently i saw a business give away food for a couple of months to offices (you can limit it somehow) but once they are hooked you can supply them basically forever as long as the food is to their liking.
When it comes to food, if you can always make that extra effort to customize the food to the exact liking (eg. i like onions in my sandwich) that can make recurring customers.
Also, working with a company that is synergistic to what they offer such as seminar halls etc. You need to go out there to find ways of getting customers through relationships with other companies.
I will stop now
