Thoroughout the island, you will find a wide and wonderful variety of hand-made objects in wood, leather, horn, metal, stone, mineral, clay, cloth, feathers... Several sections of the Zoma market in Antananarivo (behind the former City Hall, for instance) are devoted to Malagasy crafts.
When buying anything of significance (say, more than $5), ask the merchant to give you a "certificat de vente"; this is a form describing the products sold and signed by the merchant. The Customs officer may be asking you to show the form when you leave the country. One reason for this paperwork is to prevent antiques to leave the country.
Prices are low. Bargaining is common and usually expected. Since there are not many tourists, it is a buyer's market. The decent tourist will keep in mind that for each dollar saved by bargaining, the merchant loses the income of several hours of labor.
Madagascar Tourism