I like Stephanie Cave's book and I really liked "Vaccinations: A Thoughtful Parent's Guide" by Aviva Jill Romm. (It's available at Powells.com, which you can access from a link on the right side of the Mothering home page. I believe a percentage of the proceeds goes to Mothering if you access Powells' site that way.)
Romm's book is a "heavier" read, but I liked it nonetheless. It has tons of info about the vaccines as well as the diseases. It's not so scientific that a regular person would be lost, it's just incredibly detailed. For that reason, I use the book as a reference often when I have a vax or disease question. Romm's book also offers suggestions for minimizing vaccine reactions (Cave's book does this, too, but Romm's includes more options, like homeopathy). Romm is an herbalist and a midwife by profession.