The long slender one looks like an East African spear butt (as used by the Maasai and nearby peoples). For some examples of such butts, see http://www.vikingsword.com/vb/showthread.php?t=21630
I wonder if the spade-shaped one is also a butt. Veleanu's book has mis-identifications aplenty. In particular, the double-page spread that supposedly-Khmer spade-shaped appears on also has 4 late Qing spears described as 12th-14th century Cambodian spears, so I don't have much confidence in the spade-shaped one being Cambodian.
As for the last one, the one that is definitely a spearhead, it could well be from Assam. Spearheads of similar profile are made in the Congo basin, but the transition between head and socket is different. I've not had a close look at an Assamese spear, but I think it's more likely than Congo.