qgis - Create a new layer from overlap between two layers?

I'm new to desktop GIS, and will try to ask while lacking the proper terms from the GIS lingo:

If QGIS was like Photoshop I would like to make a selection from one layer, and then match that selection to another layer to get the overlap between the two and create a new layer from this overlap.

Formulated in another way:

I want to select all land from each of the Norwegian municipalities. In the shapefile I have (you can download it here: http://www.statkart.no/?module=Files;action=File.getFile;ID=41973) municipality borders are found as "N5000_AdministrativGrense" (just the borders) and "N5000_AdministrativFlate" (borders and the land within each municipality). This data (borders and land per municipality) is too administrative - it includes ocean and we have a lot of fjords in Norway. I need the landmass minus ocean.

The landmass is found in the layer "N5000_ArealdekkeFlate" - or so it looks to a novice at least.

So - I want to find the intersection between the landmass (only land, no ocean) and municipality borders and make a new layer that is all municipalities without ocean.

I'm on a mac with QGIS as my installed tool. All tips, pointers and help is much appreciated.

Answer

You can do it with the Vector tools built into the newer versions of QGIS.

I am using 1.8 at the moment, and it has a Vector menu.

Got to: Vector > Geoprocessing Tools > Intersect.

Alternatively, you can probably devise query on the attribute table that will select just the features you want. Once selected you can export that to another layer.