I've dug, and googled, and searched for posts and information regarding this topic, and I have read several past/closed discussions about it.
I've spoken with a few folks ingame about this also. (Regnaw has been IMMENSELY helpful, btw - thank you, Ren!)
What's irking me is that the [bleeping] things just aren't dropping for me. I've been killing *lots* of 'upper tier' (18-22) undead, pygmies/ogres, and skulks (among other semi-intelligent types when/wherever I find them).
I'm seeing all kinds of hoard loot, (other) formulae, techs, 'oddity' pieces, tech components, crystals, and refurbished weapons and armor. I'm seeing the invisible chain and plate (helmet and mask) forms drop now and again (and from the formulatron in Dalimond) - but I haven't looted any others but the 'Beginner Chainmail Bracer' formula (which I've looted three of) out of all these kills.
I bought the forms I do have scribed (about 2/3 of the beginner platemail, and a little less than 1/2 of the chainmail, sets) from the consigner in Bristugo, so I have to assume that they are dropping (or at least that they have dropped) for someone - they just aren't dropping for me.
(/rant off)
If anyone on Order has or finds extras of these formulae (off the top of my head I'm not exactly sure of which ones I still need), I'd be happy to pay or trade for any that I don't have yet.
(I'll worry about procuring Journeyman and higher plate- and chainmail forms when they're scribable for me, and if/when I determine that they're as hard to come by as the Beginner forms have been.)
Thanks,
Sigmound Shoebuckle