Heritage Tours was created by Joel Zack in his New York living room in 1995. Now Zack has offices in Spain, Turkey, Morocco, and South Africa, with a network of architects, designers, and historians who act as guides. "We can do almost anything that's legal," says Zack, whose specialty is the well-thought-through customized trip with access to very special people and places. Prices vary, but count on $2,000 as a start. 800-378-4555, 212-206-8400; www.heritagetoursonline.com.