How to make building blocks in photoshop

I was wondering how to make buildings for a city i'm thinking of making on photoshop. If anyone would be nice enough to inform me, I would appreciate it very much.:lol:

Well, maybe one of this tutorials can help?

http://www.cartographersguild.com/sh...light=building
http://www.cartographersguild.com/sh...light=building
http://www.cartographersguild.com/sh...light=building
http://www.cartographersguild.com/sh...light=building
http://www.cartographersguild.com/sh...light=building

I think all of them are for Photoshop, but I didn't check them all :)

(I did a search in the tutorial section of this forum on "building")

Thanks alot. And by the way.....your cities are outstanding.:lol: