What is a Sponsor? A Sponsor is someone that has the authority, the resources, and the desire to achieve a goal or resolve a corporate challenge.
See the easy project definition summary that I found - http://tiny.cc/HqZMG
Why do you need a Sponsor? Document Management and Business Process Management projects are complex in nature and require the cooperation of many people within the organization who are often in different departments. Without having a sponsor, it is very difficult to get all of those involved focused on the same goal. Usually they will have competing goals. That′s why the Sponsor needs to be high enough in the organization to have the authority to gain the team′s cooperation and also set the goal for the entire group of people involved.
What happens if you don't have a Sponsor? Nothing! Well, not exactly, but it seems like it. Your project moves along slowly, starting and stopping. You spend months arguing with the other departments because your project is going to cause them to have to work more or worse, it might eliminate the need for them. Years go by and you are still talking about what it would be like if you could just...
How do you find one? It is not always easy. If it was, anyone could do it. I think the best way is take your cause up the management chain until you reach a level that is above all of the departments involved. You also need to be willing to share the glory with those above you since they will also be taking a perceived risk to get the project funded and off the ground. They will be bringing in their own ideas and will also have to possibly sell it higher than themselves. Start with your manager and sketch out the problem, your idea for a solution, and how it will help them. You might even want to put it in the form of a business plan where you show the investment required and the expected return on that investment. You have to sell it. Yes, I said sell. Why would they help you if there is no benefit to them? I know, it sounds a lot like politics. That's because it is. That is just the way it works. That is also how you get someone committed to the success of the project.