Contrary to popular opinion, the Kama Sutra is not a glossy coffee-table collection of sex positions and ways to use a peacock's feather. In truth, it's an ancient and holy text covering everything from genital piercings to cheating: there are chapters regarding sex work, the effects of various intoxicants on sexual intercourse, sadomasochism and much more. For something so old it really does justice to the depth and complexity of human sexuality.
The pared-down versions sold in sex shops the world over can be fun, but they're not quite the real deal--you'll have to hunt a little more carefully for a fuller translation. Flicking through the sex positions in the usual abridgements can be fun, but you'll learn a lot more from truly delving into the concepts behind tantra as a sexual philosophy.