Spui square is located just in front of entrance to Begijnhof. On Fridays booksellers from all Netherlands gather here with their treasures - interesting both for serious collectors and just book lovers. On Sundays you find here artists selling their original works of various scale. If you even don't need any, come and watch.
Schuttersgalerij or Civic Guards Gallery in Amsterdam is located next to Amsterdam Museum with entrance from Kalverstraat 92 - here you can see 17 impressive portraits of Civil guards dating back to 17th century.