There are all sorts of books out there about breast cancer and a few about thyroid cancer. Here are some which I found useful and actually managed to get through - cancer books can be very boring:
These are two books I have found which give a lot of basic information on Breast Cancer: Dr. Susan Love's Breast Book, 4th Edition and Breast Cancer: Real Questions, Real Answers by Dr. David Chan.
Another good book for dealing with breast cancer is I Am Not My Breast Cancer by Ruth Peltason, et al.
This was the only book I had in 1981 with my thyroid cancer, the latest edition is from 2003. Choices: The Most Complete Sourcebook for Cancer Information, by Marion Morra , Eve Potts. I still glance at my 1980 edition once in a while to be reminded of how far we have come in what we know about cancer - mammograms were just beginning to be recommended, etc. All the other books only show us how far we have yet to go.
For thyroid cancer, the best (and only) resources are: American Cancer Society (cancer.org) and Thyroid Cancer Survivors Association. In July 2012, Thyroid Cancer Canada published a report which discusses how unique thyroid cancer is and provides a great overview.
Best of all is Crazy Sexy Cancer by Kris Carr and her website by the same name. Because cancer is all about attitude.