Just curious, when you join a faction what do you get? Do you get a capital ship? Your own domain for a site? Nothing at all?

Do you mean creating a faction? or joining a faction?

Joining a faction depends totally on which faction you join. They all give diffrent benefits depending on what player is running the faction.

Creating a faction unlocks datacards and faction specific abilities.

Creating one. How do you know what type of ship you get to start with, which datacards you get, etc.? Or do you not know until you do it as it is random?

Yeah

Not exactly random, but you won't know in advance, no. The Admin will decide what datacards it is appropriate for you to receive. You also get the facility datacards appropriate to the faction type, which you can see on the faction creation page.

In fact, maybe you should go looking at that page instead of asking questions that might have answers there?

I believe they've said before that ship datacards won't be handed out to producers anymore unless a group goes under.

^ no more ship datacards left.