An American long-time resident in Paris, Rachel Kaplan founded French Links six years ago to provide customized tours for visitors with singular or specialized tastes. Her Web site even includes a "tour request form," where you can outline your particular needs, whether it be a tour of the sights of the French Revolution and Napoleon or the art of the Renaissance. Touring the Liberation of Paris, it turned out, presented no challenges for her. For $750 (French Links charges in dollars, not euros, which was nice before the recent strengthening of the U.S. currency), we got the full-day services of Pierre Letin, a wonderfully engaging and energetic native Parisian and speaker of impeccable English.