Visiting the city markets is the fastest way to get in touch with the people of Amsterdam. Interested in shopping for little money or fresh products to cook, there are several markets where you can go.
The Albert Cuyp market has it all which also includes cosy terraces to relax after a long day of sightseeing. For 2nd-hand stuff, (cheap) clothing and keeping up your record collection, you can go to the Waterlooplein.
Different directions tip: The Dapper Markt in East Amsterdam. Here you can find fresh vegetables, fish, meat, textiles and bike accessories. And especially enjoy the multicultural atmosphere on this market.