There is no excuse really not to have some kind of helpdesk functionality for any kind of business that involves an end-user. Even if you have a small business and are managing the support requests yourself, you will find some kind of helpdesk ticketing advantageous to use. For enterprise business, you will find helpdesk system an absolute necessity in order to save time, money, and effort tracking your support request issues, as well as to enable collaboration, eliminate duplication of effort and documenting problem resolutions for reuse.
Use Issue Tracker for Outlook & SharePoint add-in to establish and maintain a live connection between your email clients (Microsoft Outlook) and your SharePoint lists. And exploit the ability to raise and log trouble tickets from emails to your SharePoint lists. The tickets in SharePoint will inherit metadata information from the emails automatically (such as name, email address, phone number, address, problem description, attachments etc.)