By an interesting coincidence, I just finished “The Mande Blacksmiths” by Patrick McNaughton*, who spent a lot of time studying with traditional blacksmiths in the Western Sudan in the 1970s. If you don't know this already, it's a fascinating study not only of smithing technique, but also of the political, social, and religious roles played by smiths in Mande society, with particular emphasis (of great interest to you, I'm sure) of the challenges of understanding blacksmith-produced Mande sculpture (both wood and iron) through the lens of academic art historical methods. McNaughton takes a primarily anthropological approach, which I think serves his subject well. He also gives a nineteen page bibliography, which I'm sure you'd find useful!
I also just posted links to the "Striking Iron" series of YouTube videos from the Fowler Museum at UCLA:
*(McNaughton, Patrick R., The Mande Blacksmiths: Knowledge, Power, and Art in West Africa, Bloomington: Indiana University Press, 1988. Print.)