Crush 9 of the cookies to fine crumbs in food processor; reserve for later use. (Cookies can also be finely crushed in a resealable plastic bag using a rolling pin.) Crush remaining 36 cookies to fine crumbs; place in medium bowl. Add cream cheese; mix until well blended. Roll cookie mixture into 42 balls, about 1-inch in diameter.
Dip balls in chocolate; place on wax paper-covered baking sheet. (Any leftover chocolate can be stored at room temperature for another use.) Sprinkle with reserved cookie crumbs.
Refrigerate until firm, about 1 hour. Store leftover truffles, covered, in refrigerator.