What are the tokens for BLOOD_NONSPECIFIC? Is it the same as for BLOODTYPE?
BLOOD_NONSPECIFIC might not have any sub-materials. It IS nonspecific, after all. I think it's the material used for "blood spatter."
What are FILTH_B, FILTH_Y, GRIME? What is SALT?
Filth is found lying around in HFS. I think B and Y stand for "brown" and "yellow," you can probably guess the rest yourself. I think I might have seen salt in HFS too, but not sure.
Is it possible to make "X laced with Y" objects?
I think the only way of doing this is via dyeing/decorations, which you can't do at a smelter.
What kind of item is vomit? I've heard of vomit smelters.
Best guess is LIQUID_MISC, but my vomit smelters didn't make it directly. I was trying to make vomit flutes and I got puddles of vomit instead.
What kind of item is soil that you can throw in adventure mode?
Probably ROCK (not the same as STONE).
What kind of item are quarry bush leaves?
PLANT:NO_SUBTYPE:BUSH_QUARRY:NO_MATGLOSS, I think.
Has anyone tried to make bone meal? Maybe POWDER_MISC:NONE:CREATURE:[creature]?
No, that CREATURE thing won't work out. I would try POWDER_MISC:NO_SUBTYPE:BONE:[creature]
Also, this page you made is a little strange. There are already separate pages for weapon tags, armor tags, etc.
http://www.dwarffortresswiki.net/index.php/Item_definition_tokens