Historical buildings are a great source of real floor plans: guild halls, merchant adventurer hall, churches, and castles will all have a visitor's map which you can easily adapt to your game.
Another great source is archaeological digs of pre-dark ages sites: Carthage, Rome, Greece, etc... all have many great floor plans that are easy to adapt.
Catacombs exist in real life (Paris has a large one) and you can easily get hold of the maps for it. Of course, you can get mines and caves plans as well and expend those.
For example, a quick google search for "tibetan monastery floor plan" got me this temple with floor plans, photos, and explanations. You could use this as a small/medium temple in your world with great ease.
Finally, there are a lot of computer games out there with dungeons: just get one of the strategy books (or walk through) and you should have a plethora of unrealistic dungeons filled with monsters that just wait for the PCs to come and kill them.
- Figure out how relations are between the orcs and the ogres in the camp.
- Give these two groups tribal names, flags, distinctive armor, etc. Are there members of more than one clan within either tribe? If so, give each clan a name and a flag, and figure out the relations between the clans. Is there tension there? History? Pride?
- Think about how labor is divided in the camp. Are some leaders, some guards, some cooks, some porters, etc? Are jobs divided on a racial basis? Is there any resentment or ill-will there? Insubordination? Sabotage?
- Come up with one "representative" from each clan, tribe, or laborer group. This will be the one your PCs interact with, who will represent the opinions of his group. Give him a name. What does he want? What does he hate? Is he loyal to his group, or is he looking out for his own gain?
Orc name generator: http://www.rpginspiration.com/tables/OrcName.ipt
Clan name generator: http://www.rpginspiration.com/tables/OrcClanName.ipt
Ideas on Orc culture, etc: https://okam.obsidianportal.com/wikis/orcish-culture
Best Answer
The Agon island generator generates islands complete with names.
Other than that, I think any random place name generator would work, if you stick "Isle of" on the front or "Island" on the back of it.