Having a Web site is great, so long as it fulfills a specific set of needs for you. A Web site can fill many purposes. If you identify your needs, a designer can work with you to decide how to best serve those needs on your Web site. Once you've figured out what you want your site to do, you need to figure out when you want the site to be ready, and how much you're willing to spend on it. Sites can take a day or two to complete for simple designs to many months for elaborate sites with numerous features.
Costs can also range from rock bottom to top dollar.
Keep in mind, though, that high rates doesn't always imply high quality, so be sure to check out the designer thoroughly before choosing one that can meet your needs at a price you can afford. It should go on your letterhead, business cards, brochures, advertisements, and wherever else you use your phone number. The more you publicize your Web site, the more likely people will come visit it. You probably have a specific design for your brochures, stationery, etc. Your Web site should also reflect this design, so it fits in seamlessly with your other publicity elements and provides a unified image of your site.