Not, it's not something you can convert easily. You'd have to find bearing cones that fit the same bearing size and layout on the cup on the hub, but are drilled and tapped for 10x1mm threads. There might be something you can cobble together with bits and pieces of several different hubs, but I've never sat down and tried. I think all of the Shimano mtb disc front hubs that you'd be doing this to in order to run it as a fixed rear hub are like the M-756 and use a stepped 10mm axle or cannot be converted as all because they use larger alloy axles, like the newer XT and XTR hubs.

9mm is the standard for quick release or track hubs for front axles/dropouts. The M-756 is interesting because it uses a 10mm axle that steps down to 9mm where it enters the dropouts (if it were 10mm straight through, it wouldn't fit in a fork).

Of course, all of this axle swapping and what-not is unique to cup-and-cone (loose-ball) hubs, like Shimano. I have no idea what your American Classic hub is like.

I think you could get away with using the locknuts/cones/axle from a Surly rear hub with a 10mm axle in a Surly front hub if you're into Surly hubs and wanted to run a Surly Disc Front Hub as a rear fixed bolt on hub. I've not seen the guts of a Surly hubset in a while, so I can't be for certain.

Side note: you can replace the "adjustable" cartridge bearings (that don't hold their adjustment) in a Surly hub with a normal non-adjustable cartridge bearing and turn it basically into a Formula-type non-adjustable hub that won't loosen up and annoy you (which is the biggest complaint of Surly hubs I've heard). An alternative solution for people who already have Surly hubs and hate that they loosen/tighten themselves over time.

Edit: 6901 bearings are standard 12x24x6 non-adjustable cartridge bearings that are a direct replacement to Surly bearings and will make your Surly hub hold its adjustment.