Dave; German traditional archery magazine "Traditionell Bogenschiessen" (
www.bogenschiessen.de) recently featured a three piece series about steel bows (issues 47-49, 2008).
Manufacturers mentioned there apart from SEEFAB and APOLLO are CHIC and HOWE (both late 19th c.), H. M. WILCOX (patented in 1927), the True Temper bow by "The American Fork and Hoe Company" (1928-1932) and Clarence W. Grimes who in 1952 presented an aluminium bow.
More steel and aluminium bows were made by Frederickson ("Game Master"), Ivanhoe, Sederquist, the Park Tool & Die Co. in Jackson/Michigan ("Par X Bow") and Wham-O Powermaster Co.
Also mentioned is a singular and curious Sioux steel bow and one example from India.
G.N. Pant only marginally mentions Indian (Moghul) steel bows in his book "Indian Archery" but there are some b/w illustrations in the plates.
An interesting specimen of Damascus steel in the Knife Museum Seoul/South Korea is discussed
here.
I hope this helps. If you're interested in acquiring the TB issues mentioned, please try the above link. In case of problems please get in touch with me, I will try to facilitate.
Best wishes from Germany,
Jan