Open a shapefile
On this page, the use of a map of Dutch municipalities is described, like offered by Statistics Netherlands in a ZIP-file (Map files). Unpack this file in a separate folder. A series of files named gem_2010_gn1 will appear. Together these files form the ‘shapefile’ that can be used to draw a municipal map of The Netherlands. Besides boundaries it contains statistical information about these municipalities (‘attributes’). Open the file gem_2010_gn1.shp in QGIS with ‘Layer / Add vector layer …’ (or the corresponding button on one of the toolbars at the top of the window). Make sure the file type is set to ‘ESRI shapefiles‘. That will make it easier to select the right file. In this case, the character set (‘Encoding’) should be set to ISO8859-1. Otherwise, special characters like accents will not be presented right.
After opening the file, you will notice a layer has been added to the ‘Layers’ panel on the left. The map is not yet visible in the map canvas. You have to click on the selection box first. If that does not give the desired result, click on the layer with the right mouse button and select ‘Zoom to layer extent‘.
Inspect attributes
To see the statistical data on the Dutch municipalities, click on the layer with the right mouse button and select ‘Open attribute table‘ (or use the button on one of the toolbars). Close the table for the next action.
(Translation of http://sites.google.com/site/qgisnl/ervaringen-en-tips/1-vectorlaag-toevoegen)