Congratulations! You've taken undertaken an effort that will hopefully minimize headaches and issues later in your deployment.
Keep some general tips in mind about organizing this information once collected and getting support for this step in your planning process.
After organizing the fruits of your investigative work, review the content en masse before proceeding to the technical aspects of your design planning. It can be very helpful to prepare an executive summary of your findings thus far in either written report form or slide presentation form. Later, as you build your case for action to present to your oversight committee or the board of directors and so on, you can begin by showing the needs of the user install base. Most organizational leaders are more understanding of user pain and needs driving new technology than just new technology for the sake of having the latest and greatest.
Finally, it is also wise to begin looking for and recruiting project advocates within the business side of the organization. You can talk all you like about the advantages of Exchange 2000, but recruiting a few agreeable evangelists among the end-user community and especially the ranks of management can make all later deployment efforts significantly easier.
Good luck with your Exchange 2000 deployment!