Here is a simple recipe for grilled Corn on the Cob from ATK. I used a similar technique a lot last year where you peal back all the leaves and remove the silk then re-wrap the corn and tie it closed. The technique below sound like it will be simpler and may give you more of a "grilled" result as keep all the shucks on protected the kernels quite well.
Ignite about 6 quarts charcoal and burn until coals are completely covered with thin coating of light-gray ash. Spread coals evenly over grill bottom; heat to medium-high (you can hold your hand 5 inches above grill surface for 3 seconds); position grill rack. For the gas grill, turn it on high covered for 10 - 15 minutes.
Meanwhile, remove all but innermost layer of husk from each ear of corn (kernels will be covered by, but visible through, last husk layer). Use scissors to snip off long silk ends at tips of ears.
Grill corn, turning ears every 1 1/2 to 2 minutes, until kernels have left dark outlines in the husk and husks are charred and beginning to peel away at tip to expose some kernels, 8 to 10 minutes. Transfer ears to platter; remove and discard charred husks and silk. Season corn with salt and pepper and butter to taste; serve immediately.