I've walked the Inca Trail alongside people who paid $8 to hike it (old student fee) and people who paid $800 (on a really expensive tour), and I can honestly say that they all seemed equally thrilled. Hiking the rail independently or with a few friends you may have met in Cusco gives you a feeling of true accomplishment. But there is something to be said for doing it in an organized tour as well, especially when it comes to the delicious food prepared by tour cooks after a day of strenuous hiking. Finding a tour agency in Cusco is not hard, they are located all around the Plaza de Armas, especially along the Procuradores and Plateros streets. However, finding a good agency is a bit harder. Cheapest prices do not necessarily reflect the best deals and expensive prices do not automatically represent the best quality. Here is a list of reputable companies who I know provide good service, the first being most affordable and the last most expensive: UNITED MICE (Plateros 348, tel. 221139); LUZMA TOURS (Santa Teresa, 261327); RIKUNI TOURS (Plateros 341, 241700); INCA EXPLORERS (Calle Suecia 339, 239669); PERUVIAN ANDEAN TREKS (Av Pardo 705, 225701; LIMA TOURS (Av Machu Picchu D24, 228431).