what are the laws about a sales person working for another company and contacting leads from the previous company? Non-compete was never signed.

Generally, a former employee is free to make sales calls on prospects of whom he learned while previously employed by a competitor. Indeed, the employee's familiarity with the industry and the sales prospects will often be precisely why such an employee is hired by the new employer; and it is the public policy of the United States to encourage employees to be free to change employment to maximize their value to new employers and themselves. There may be limits on the use of the former employer's confidential information. For example, an employee may generally not leave employment and take customer lists with him. These limitations generally do not prevent the employee from using his own memory or from using information generally available to those in the industry. In the event of a serious questions, the new employer should consult with counsel.