You can find a small number of datasets on the Geoplaza website: some georeferenced or even vectorized maps, information about licensed data or datasets created by researchers of the Vrije Universiteit.
The map series database
In the Map Series Database you can find an overview of all published map sheets of important Dutch map series and an inventory of map sheets in the University Library’s collection.
On the web
Also of interest are ESRI ArcGIS Content where you can find a lot of the PDOK datasets in ArcGIS formats and also a free version of the Postcodevlakken data.