Creating a Dungeon in Photoshop Tutorial Request

[Midgardsormr]

I don't have time to offer much, but do a search for Duvik's tutorials. The basic gist is to establish your grid (he uses a pattern fill), then use the marquee selection tools to create an alpha channel that defines your walls. From there, you can fill the selection(s) with textures and use layer effects to create glows, bevels, etc.

You might also look up Overwatch's tutorial on painting floor tiles.

As for populating the dungeon with prefab objects, I think I mentioned recently elsewhere that you can clone stamp from one document to another. So make an image that has all of your objects arranged so you can sample them easily, and make sure the background is transparent. Create a new layer in your dungeon document, and start clone stamping the objects into it. If you need to move something, you can just lasso it and use the move tool. If two objects will overlap, make a new layer for the top object, so you can retain the ability to move it independently.

edit: The first tutorial listed by RobA below is the one by Duvik that I was referring to.