Based on the results of my cookie texture poll, most people--myself included--prefer chewy cookies over crispy cookies.
But if you really want to bake some crispy cookies, check out my earlier post on getting the mouthfeel that's right for you. Or, for more info and suggestions on how to achieve the texture you desire, check out this page from the Quamut guide to baking cookies.
While I do prefer chewy cookies over crispy cookies, I think the perfect texture is a mixture of both: a crispy exterior and a chewy interior.
I've found that the best way to achieve this texture balance is to roll the dough balls in turbinado sugar before baking. For example, I used this technique with my Better Than Grandma's Oatmeal Raisin Cookies (pictured here), and they turned out perfect!