An important part of any project is figuring out who else to talk to, to work with, to learn from, and to collaborate with. A real challenge is balancing your investment in mapping, understanding, and interacting with stakeholders with all the other important components of your project. You don't want to spend all your time talking to people!
That said, project managers and participants often underinvest in this external activity. The work on X-Teams (page to come) presents evidence on the importance of this part of your project work, because not only can it help your results to gain acceptance, but the information you gather and relationships you build can help you get your project work done better and faster. It can change the course of your project and dramatically alter the amount and type of work you envision for your project at its outset.
How does this apply to your project? To get going, you'll want to list the people and groups that you think matter to your project, and then to analyze what you know of each in order to come up with a plan for approaching them and building relationships. You will need to prioritize your list of stakeholders and note who you are targeting and a few words on why; also list who you are not placing at the top of the list, and why. Such notes can be invaluable during your project "post-mortem."
Now, for the actual mapping of stakeholders. Where to start? I've gathered a few resources. Tools for analyzing stakeholders abound: checklists, excel spreadsheets, etc. And, of course, there many assumptions built into such tools and frameworks (often unstated). We'll want to at least touch on some of these issues in a future discussion. But for now, you are going to learn by doing--so give one of these a try!
There are plenty of practitioner-oriented resources to draw on. One recent paper on planning and carrying out these external activities presents a "stakeholder circe" framework you may find helpful: Achieving a Successful Engagement. From the world of information technology come many potentially useful tools. Consider this detailed overview, Project Clarity through Stakeholder Analysis, which explains the rationale behind the proposed approach. Note that you can click on each image to see it more clearly. This piece should give you a sense of how stakeholder analysis is used in projects.
For a ready-to-use tool, here's an interactive framework: Stakeholder Analysis Worksheet from IT Toolkit. A similar workseet, Stakeholder Mapping, from ChangingMinds.org also shows some links to a simple model of change that may be useful for you.