The pile of new spiritual literature is growing like a landfill full of disposable diapers; they serve the purpose for a couple of hours (in much the same way) and then need to be thrown out - because unfortunately they don't evolve, can't be reused, and are too difficult to recycle. Some of these books pollute our social environments longer than the half-life of plutonium. Witness the ongoing success of the ubiquitous bestseller, The Celestine Prophecy.
Arguably, aspects of our post-modern society create a void of spirit and meaning in many people's lives. A number of trends work to fill this void: rising religious scrutiny and criticism; increasing interest in old faiths and paganism; obsessive "success and empowerment" speakers and workshops; and attractive social, environmental, and even separatist movements. Leading the hordes are a bevy of self-styled gurus and marketing wizards.
More and more, people are cobbling together their own personal faiths from what they remember from Sundays as children, books read (bought, borrowed, or referred), with a dash of Ann Landers and a few bumper sticker sayings thrown in for good measure. Homebrew spirituality may work, but only if it is started with the right ingredients. Study the classics - the Bible, the Koran, the Bhagavad Gita. Read some Eastern philosophy - Confucianism, Buddhism, and Tao. First find some substance, then add the sauce and spice afterward.
Even if you don't feel up to the classics, all modern and/or new age spiritual literature isn't garbage. Thomas Moore's Care of the Soul is a deep refreshing well, where Redfield's The Celestine Prophesy is a Mr. Turtle Pool. Wander through Carlos Castaneda's maze before skipping down the lane with The Way of the Peaceful Warrior.
Bad new age literature is like fast food. If you have a balanced spiritual diet a little Celestine can't hurt, and might even be tasty and fun (even though you know it provides nothing but empty calories). A drive-thru burger is nectar to someone who has never eaten decent food. But if fast food is all they ever eat, they will be unhealthy, get sick, and ask, "I just finished eating... why am I still hungry?"