Dwarves in LotR are short, aggressive and bearded. They are fine warriors and craftsmen, but are known to often be motivated by thought of personal gain. But aside from their slightly greedy nature, many also are known to be honourable and courageous.
LotR dwarves are very rare, as PPC agents go, but there are a few, the most notable being Justin Agent. Like Justin, they rarely use their real names, due to their secretive natures. They usually take their names from the languages of Men living near them. This tendency is evidenced perfectly by Agent Jane Doe.
Generally dwarves are cast as Designated Misogynistic Bastards or forgotten entirely, because they are not attractive. Actually, they are incredibly resistant to Mary-Sue-influenced lust, to the point where Mary Sues and suefluence do not repel them, but they repel Mary Sues. This curious property is what prompted the research and development of the medication Anti-Lustin-- which is derived from dwarf blood samples. This appears to have changed to at least some extent with the release of the movie version of The Hobbit, as Sues now often go after members of Thorin's Company.