I've started doing some of my own speed paintings.
This brush pack was made to make my paintings a little easier. i hope you find them useful for blocking in some background buildings or throwing up some steel structures.
Chimneys, Smoke Stacks
Street Signs and Street Lights
Dirt, Mud and Grass
Building Texture brushes
And many more i haven't listed.
There are over 150 brushes in this pack.
I hope they come in handy!
(I made these brushes in CS4 so they'll work in all CS editions of photoshop i presume, not sure about the earlier versions. you'll have to try for yourself)