Since I’m a graphic designer I'm obviously into books and my favourite bookstore in Amsterdam is Boekie Woekie. This small shop is located in the Nine Streets and they sell nice and special publications that are often hard to find because they are self published or published by small press publishers. If you are into graphic design you should really check it out.
I love how small this place is, but it offers such amazing quality in cheeses, meats, wines, bread etc. You can also have lunch here. Definitely worth picking up fresh food here!
The Bartolotti is perhaps one of the most beautiful Museum Houses Amsterdam has, built by someone who once was the richest man in the city, but it's a bit hidden in plain sight. These days, it is run by a group of lovely old ladies, who can't wait to offer you tea or juice. You can walk around the house like you live there.
You have to ring the doorbell to get in.
(picture from Google, by Arjan Bronkhorst)