Which small business sector would most likely have a website? -

An Internet Web-Site Design Company - Easy!

The best answer that I can give is all business sectors are likely to have a website of some sort. The internet has leveled the playing field for entrepreneurs like nothing else before. There are established communities for every sort of niche market imaginable. If you are thinking of a specific business to begin or promote, no matter how small a niche you might think it is, just type in the term into Yahoo Search and see what comes up.