Recommendation: first big book on the codes, mandatory reading for background understanding
When The Bible Code was published in April 1997, it became the #1 worldwide best-seller with over 22 million copies sold around the world. Michael Drosnin took a lot of heat for his book, from both the critics and from the top codes researchers. It didn't help that as an agnostic jewish journalist, he postulated that the Bible and Bible code may have been created by aliens. I guess if you're agnostic, then you grasp for any possible explanation except the existence of God as revealed in the surface text of the Bible.
However, I have never criticized Drosnin's book too much, because he did a good thing in bringing the subject to a wide audience around the world. As a journalist he had a much better feel for presenting the topic than a scientist would, whose writings are often dry, overly filled with mathematics, and not easily understood by the general population. Did Drosnin claim too much? Yes, but that is often the achilles heal of journalists schooled in using sensationalism to draw in an audience.
Have the Bible codes progressed far beyond the simplistic 3-7 term matrixes in The Bible Code? Yes, we've gone way beyond these beginnings, and are now using phrases and sentences. Today's Bible code matrixes are statistically light years beyond The Bible Code. I think Drosnin's book reads fast, is reasonably well-written, and provides the necessary background to begin exploring the Bible code. Therefore, I think reading The Bible Code is mandatory, although it is in practically every public library, so people can check it out for free at the library.
The Bible Code and is available at Amazon.com and Barnes&Noble.com in both hardcover and paperback and one can buy used copies very cheaply. It's also available at most large bookstores.