1) Yes, up to 4 sites per prov on the map. This includes mines, and sites that give you a lab or fort. Random events can give you another site, mostly mines, if there are less than 4 sites currently in the prov. You can get free labs and temples from events even if there are 4 sites. Temples have nothing to do with sites.
2) Yes your global does a DRN dispel if there are already 5 up, and yes it is completely random which of the 5 existing globals it will try to replace, your own global is possible.
3) Under enemy dominion your units have reduced morale. You do not get any positive income/resource/luck/research benefits from scales. Your god and pretender will be weaker. Some enemy globals will be more effective in enemy dominion.
4) You can guess who's doing it based on the paths required. Also remote rituals where an army is summoned that you get to keep (Call of foo, Arouse Hunger, Horde from Hell) will identify you in the battle screen.
5) Top to bottom in the battle setup screen ('t' or 'y'), except spells are cast first during each combat round, and commanders go before troops.
6) Protection is applied to every attack that is not armor-negating. It is not reduced by hits, except for special attacks that destroy armor.
7) 5 fatigue per cast from an item.
8) Flyers have less change of making it all the way to the rear when there is a big army in the way.
9)
The Dominions 3 Faq & IRC Channel Info