The Internet is one of the best tools your firm has to target new prospects and keep existing clients happy. But before you begin reaping the benefits of e-marketing, you have to collect a database of e-mail addresses. The Internet is an essential tool in the management of a progressive CPA practice. Whether your firm is communicating with clients, filing tax returns online, creating an "Intranet," or launching an e-marketing campaign, one thing is clear: You must collect and manage a list of e-mail addresses. At first glance, this seems like an easy task.