Can you land your former employer as a client? If your new business doesn't compete with the company you used to work for, and you've been a hard-working employee, your former boss should welcome the chance to become your client and refer friends and associates to you as well.
Should you tap your former employer's customer base? If you signed a noncompete contract with your former employer, you're obligated by law not to solicit its clients. Noncompete contracts generally have a time limit--say, two or five years--after which you're free to target the company's clients.
Whether doing so is a good idea depends on your local business climate. In some communities, soliciting a former employer's customers is frowned upon; in others, it's totally acceptable.