The books published by NOLO (below) are written for non-lawyers and they are very helpful. But they are not about New Hampshire law. Use them for introductions to the topic, and then double-check any information you find by consulting New Hampshire sources.
Please remember that this guide is for information purposes only and is not comprehensive. It is intended as a starting point for research, to illustrate the various sources of the law, and to provide guidance in their use. NH Law About ... is not a substitute for the services of an attorney.