You can't go wrong with Cusco's Internet cafés. They are everywhere in the Old City -- all display an @ sign -- connection times are fast, hours are late, and the price is dirt-cheap at S/1-2 per hour. Intinet, Mundo, and Telser are three of the many good bets.
SERPOST, the national post office, is open Monday through Saturday 7:30 AM-8 PM and Sunday 8-2. Anticipate about two weeks for your cards to reach the United States or Canada; a few days longer for Europe. (Mail arrives more quickly if posted from Lima.) For important packages, DHL has an office in Cusco. Scharff International is the local representative for FedEx.
SERPOST (Av. El Sol 800. 084/225-232).
DHL (Av. El Sol 627. 084/244-167). Scharff International/FedEx (Pardo 978. 084/226-162).
Intinet (Choquechaca 115. 084/245-157). Mundo (Santa Teresa 172. 084/260-285). Telser (Calle del Medio 117. 084/242-424).
