There are several shops, mainly Inca souvenir types. A market plaza for tourists sits at the entrance to the ruins, small shops up the hill from the plaza may carry the same items and be more willing to negotiate.
On the way from the ruins to the plaza, look out for the Awamaki Fair Trade Store (http://www.awamaki.org) after the bridge on your right hand side. Emphasis is on fairly-traded weavings from the Patacancha valley made with 100% natural fibers and dyes, as well as a select range of books, alpaca yarn and other locally produced artisanal items. The project is non-profit and proceeds from the store are invested into community development projects in the Patacancha Valley.
