Well, this is certainly a sad thing. But first, email or phone the other maker and ask him what's going on. Maybe the site where the knife is listed for sale made the mistake, or intentionally miscredited the steel in order to improve its profit margin. A sole authorship knife is worth much more than a knife made with someone elses steel (at least to me).
Tell the maker you expect attribution for All of the steel you made for him. See if he does the right thing.
If that doesn't work (and very quickly), let the site where his knife is listed know about the situation. If the maker or the web site refuses to acknowledge his use of Your materials, contact the Guild and/or the ABS if appropriate. Even consider outing the makers name here in the Good, Bad, and Ugly forum.
I am interested in sole authorship work. So a knife presented has having been forged by a particular person should have actually been forged by that person. If a maker wants to use someone elses damascus (as is so common in the folder world), the maker of the steel should receive credit for his work. And that is true when the steel was Paid for. When it is a gift, and someone fails to acknowledge you, it speaks very poorly of the character of that maker.
Assume it was a mistake and see if it can be fixed. If not, out the name. I take it there is enough steel that this fraud could be perpetrated several more times. I am sorry to hear about this. But I'm still not sure exactly what has happened. I understand your shock and dismay, but I'm hoping there was some sort of innocent mistake made here. If not, let us know who this unfortunate character is and we will take care of him
Paracelsus
[This message has been edited by Paracelsus (edited 09-14-2000).]