1. They only care about price.
Not in my experience. Usually that's an excuse made by those who aren't really innovating. Offer a small business owner a killer feature that genuinely makes his life easier and he will switch. Price your product fairly and competitively, but there really is no need to give away the farm.
2. They're slow to adopt new technology.
Another lame excuse, which derives from a lack of attention to EASE OF USE. The interface, the logic, the value proposition, each of these needs to be simple and clear. That's why the guys at 37signals are doing so well with alternatives to mainstream productivity apps, because, to paraphrase Colin Chapman, they simplify then add lightness.
3. They aren't sophisticated.
Are you kidding me? Most small business owners and employees do more multi-tasking in a day than the average big company middle manager does over his entire career. That's why they make such great customers, because they are quick to embrace change that helps organize the chaos of doing so many things at once.
4. They don't respond to marketing.
Probably because they've got better things to do. Seriously, though, all this means is they can't be tricked by the slick pitch. And if you've got a great product that solves a real problem, then a slick pitch is the last thing you need.
Really, small business customers are the best kind. They buy if your product is compelling and does what you say it will. What could be simpler than that?