Originally Posted by Danny B

This should get you started ;)

DJ STUFF

By far the best shop in the country. You can sit there all day, smoke and listen to everything they've got. The crew is very helpful and most of them are professional dj's who work there just for fun.

Outland Records: http://www.outlandrecords.nl/

Runners up:

Killa Cutz: http://www.killacutz.nl/
Midtown records: http://www.midtown.nl/

DJ School:

http://www.amsterdam-dj-school.nl/