Hi, you had wonderful information about your ancestors, and Harold did a fantastic job of pinpointing more for you.
Drangedal municipality has a published "Bygdebok" - a farm and family history book which will tell about your ancestors.
There are online lookups volunteers who are willing to do some limited lookups in the books, which they own.
At this website, after it loads, scroll down a bit, click on Telemark, and that will scroll you down automatically to the Telemark section of the page. There you will find three lookups volunteers with the Drangedal Bygdeboks.http://www.rootsweb.com/~wgnorway/lookups.html
Here is also another page showing lookups volunteers who own Bygdeboks for different municipalities in Norway.
Three (perhaps the same three) are also named for Drangedal and Tordal.http://members.tdn.com/dagwood/lookups.html
Good luck! Using the Bygdebok, depending on the information, you may even be able to follow the path to relatives still living in that area today. If you can get their names from the Bygdebok (which also may be available to you through an interlibrary loan or at a nearby university collection) and their birthdates, it is possible to find them on the white pages for Norway (address and telephone), and verify using the online Tax lists for Norway.