Dagga is a mild relaxant. It provides a mild sedation, and a calming effect. Largers doses can show mild visual distortions, however, Wild Dagga should not be smoked for a "high". It is simply mild and wonderfully relaxing. Trying to get "as high as possible" will only lead to disappointment. If you enjoy the sedation and relaxation of small amounts of cannabis, but hate the "high" dagga is a good choice.
All of the daggas are known for potentiating other herbs and smoking blends. Many smoking blends take advantage of this fact, such as Diggity Dagga from Herbal Smoke a product which contains 3 different types of Wild Dagga.
All most all vendors have wild dagga. IAS has very good Wild Dagga and Wild Dagga resin.
MJB sells Wild Dagga resin as well.
The best way to buy dagga is dagga flowers, by far. The cheapest dagga flowers seem to be on http://www.vegetalistabotanicals.com/ . The flowers are better than resin.