We know that the universe has more dark and anti matter as compared to normal matter. Can there be dark matter galaxies or antimatter galaxies?
Dark matter galaxies are possible but very speculative. On a theoretical level, they are hard to form because dark matter interacts only gravitationally (see Anders Sandberg's answer), which makes it hard to lose energy and become bound structures. On an observational level, they would be hard to detect. Gravitational lensing can do something, but since one cannot actually see the galaxy, it's also hard to say where the dark galaxy is -- if there is one at all.
Still, people have studied the idea, so it's not impossible.
Antimatter galaxies: At some level the idea that there are antimatter galaxies out here is appealing. First it can solve the baryon asymmetry problem at a stroke. It's also the case that an antimatter star would shine. From long distance, it would also be practically indistinguishable from a "normal" star.
However, there are strong reasons to believe that there are no antimatter galaxies. That's because antimatter annihilates with normal matter, which leaves experimental signatures. If any part of the Earth were made of antimatter, it would immediately vanish in a flash, so we can be sure that the Earth is mostly matter. Similarly, if the Sun were made of antimatter, we would be quickly annihilated (thanks to the antimatter solar wind radiating from the anti-Sun), so we can be sure the Sun is also mostly matter. Similar arguments allow us to conclude that the Milky Way is almost entirely matter, the Local Group is almost entirely matter, etc, all the way up to the largest structures in the sky.
If antimatter galaxies exist, they are probably outside our observable universe, at which point some will argue it's no longer science.
Probably not. Dark matter should really be called "transparent matter" since it does not interact with light. This has an important consequence: it is hard for dark matter - whatever it is - to lose energy by radiating. This is why normal matter can form clouds that accrete into dense regions that in turn become galaxies and stars: energy is radiated away. But dark matter cannot do this as far as we know, so instead it forms large diffuse "halos" that surround galaxies.
Antimatter is completely different from dark matter. For some reason (important research topic) there is far more normal matter than antimatter in the universe, and all primordial antimatter is likely to have reacted with the matter in the early eras. Hence there are not going to be enough of it to form antiplanets, stars or galaxies.
Gravitational lensing observations suggest that there is a large mass of dark matter on either side of the bullet cluster, which is actually one of the major pieces of evidence that dark matter does indeed exist. This dark matter essentially "left behind" the majority of the normal matter in the galaxies it was with as two galaxy clusters collided and most of the normal matter in them got tangled up in the middle. These globs of dark matter with little normal matter probably could, if you like, be considered (in a non-technical sense) to be dark matter galaxies. They're not 100% dark matter, as most of the galaxies' stars also went with them, but they are, at least as I understand it, more dark matter than not.
This isn't the only such object; a similar collision between galaxy clusters produced the object MACS J0025.4-1222, which also consists of several galaxies worth of dust and gas stripped of their dark matter with a pile of dark matter and stars on either side.