To retrieve a list of the current WvW matches you first have to create a new instance of the WvWManager class. The WvWManager manages all relevant object and ensures that the cached data is used.
The WvWManager resides in the GW2DotNET.V1.WvW namespace. Create a new instance of the WvWManager class with the following code:
GW2DotNET.V1.WvW.WvWManager manager = new GW2DotNET.V1.WvW.WvWManager();
Note: You can also add the GW2DotNET.V1.World namespace to your using directives.
To retrieve the worlds you now call the Matches property on the WvWManager and convert it to a list (or other suitable collection).
var matches = manager.Matches.ToList();
You now can use LINQ or any other method to iterate through the list and get single matches.