Mabby, The main admin page is reached by browsing to
http://192.168.0.1
According to
this Dlink page, the default user name / pwd are 'admin' & blank pwd.
Try following the instructions on this page to see if you can get a connection.
You will need to have a connection to the router to access this page.
If still no luck, there are a couple of other things to test -
In the router admin web page, click on "status" and write down the contents - in particular does it show a WAN address beginning 82.x.x.x.