Microsoft adCenter can help you reach potential customers and drive them to your site. (Try it now and you could qualify for £50 worth of free clicks!) It's an online search platform which serves ads across Live Search. The advice is start thinking like one of your own customers - what do you do when you're trying to find something? You go online. You click on an online ad for a site that potentially, can sell you what you want. So if a customer is trying to find your product, how do you get your website to appear in that customer's search?
The report (Search Marketing for Small Businesses) is enlightening - you really don't have to spend a fortune and you decide how much you want to pay. You can track click-throughs and even conversions, and assess how successful different ads are.