Other than Gimli, I assume?
The Dwarves of the Lonely Mountain came to the aid of Laketown against the forces of Sauron.
From Appendix B:
At the same time as the great armies besieged Minas Tirith a host of the allies of Sauron that had long threatened the borders of King Brand crossed the River Carnen, and Brand was driven back to Dale. There he had the aid of the Dwarves of Erebor; and there was a great battle at the Mountain’s feet. It lasted three days, but in the end both King Brand and King Dáin Ironfoot were slain, and the Easterlings had the victory. But they could not take the Gate, and many, both Dwarves and Men, took refuge in Erebor, and there withstood a siege.
Other than that, there weren't significant populations of dwarves in the contested areas - the known dwarven realms besides the Lonely Mountain at the end of the Third Age are in Ered Luin, the Blue Mountains near the Shire, and in the Iron Hills north of the Lonely Mountain (although how many remained there after the Lonely Mountain was established once more was unknown). Dwarves from the latter probably would've come to the aid of their brethren in the above battle if they had time.