One of most common question asked by the users of the Outlook Custom form is How to simplify the process to open Custom Forms in Outlook?
Below mentioned articles describes various methods that you can use to make a custom Outlook form more accessible to users:
How to simplify the process to open Organizational Forms in Outlook
How to Open a Form from a Toolbar Button
However, there is a know issue when distributing the VBA macro code to other users as per article mentioned below; so creating a small COM/VSTO add-in is way to go.
Code Does Not Work After You Distribute a VBA Project
In order to know how to develop an COM/VSTO Outlook add-in refer to KB322145 Section: Creating a Component Object Model Add-in Solution.
Hope this helps!!! Have great 2010!!!