The best way is to spend time in your local library looking at books there. Or to search the WWW for 'ailments herbs' and see what you come up with. I have numerous books which list ailment-herb, but none is entirely satisfactory to myway of thinking. So you might have to do what I've done, and compile your own book, listing ailments and remedies for each (no, it's not published).

An important thing to remember when choosing a book, or putting together your own, is to make sure you've got information on which PARTS of the herbs are used, and how they're used (so you'll have to hunt up recommended dosages). Too many books will say that X herb is good for Y ailment, or that to treat Y ailment, X is a good herb, but it's useless information without the detail.

Also remember that it would be almost impossible to list every ailment known to mankind, and that there are 20000 known herbs on the planet. Any book you'll find will just list the tip-of-the-iceberg.

The following site isn't a bad place to start your own research.

Here is a link that might be useful: ailments and herbs to treat them

Search at Google for "Michael Moore" and herbal medicine

The 1927 Materia Medica at his site is really good, and he has a lot of other references.

A terrific reference book for what you are seeking is David Hoffman's, "Medical Herbalism". David has been a practicing medical herbalist for over 20 years. He blends a scientific knowledge with traditional folklore and empirical knowledge. He knows what works and what doesn't through his vast experience. This book is huge - at 666 pages. He starts with a thorough coverage of phytochemistry and then proceeds to divide the book into systems of the body: digestive, cardiovascular, respiratory, etc. He discusses disorders and herbs to help (everything from teas to tinctures to aromatherapy). He also has a terrific materia medica. I believe Bastyr College and Tai Sophia Institute use his book in their master's programs. I can't recommend it highly enough!!