After reading your committee's background guide, you should become familiar with the commmittee itself--its purpose, its members and its level or scope of influence or jurisdiction. It is best to know WHY your committee is discussing a certain topic, so you can better understand HOW you can best come to a resolution on that issue.
The
IRO Handbook provides descriptions of the main organs of the United Nations, including a chart detailing the structure of the UN itself. The following links may be helpful when participating in a UN committee:
The following links will lead you to some of the more prominent specialized committees at found at MUN conferences. For committees that are not found here (or for cabinet committees), a simple google search will help you begin your research.