1. Planets and Moons... what are they for? I see lights indicating cities on many planets, no idea what I can do with them, anything?
Planets are just there for visuals and to maintain the size "feel" of EVE. Cool city lights though, eh? Rumor has it that sub-orbit capability will be added later for planet bombardments. Moons are used to help Player Owned Stations (POS) mine for certain types of minerals.
2. Is there any sort of limit to how many assets I can have sitting around in various storage bays on various starports?
Not that I am aware of, no. There is not a limit.
3. Is there anyplace in generaly where Tourists can be dropped off at? There was this unfortunate incident with this Pirate Casino and now I have a mess of tourists sitting in a storage bay... the smell is getting a bit irritating.
You could always collect and keep them, just in case a mission/objective calls for tourists and you lost the origonals. Otherwise not sure.
4. Dog Tags and Criminal DNA. I know that agents will periodically ask for the latter, but is there anyplace (Concord or DED maybe) that will routinely take these?
You can sell dog tags on the market, but it's not very profitable. Hold onto both, and save both as dog tags in the future will be the basis of MANY agent offers to give you incredible items.
5. I had a rather... unfortunate... incident with a group of Calderi NPC's with missile frigates. Any suggestions on dealing with this in the future (other than running)?
Depends greatly on what race of ship you are flying. But, in a general answer, find a way to tank the missiles. If they are thermal based then setup your shield or armor tank-setup with thermal resistances. If they are EM based, then setup your shield or armor tank-setuo (which ever you are using) with EM resistances. They use the same missiles/rockets as we do, so when you check your logs to see what type of missile hit you, you know what type of damage they do. Generally, you can also get that information at: