Attitude, Google, 150 wires...let's throw all that out.
The main piece missing here is how you want to arrange these LEDs. How bright are they, should they be clusters or single LEDs, how far apart should each pixel be, how bright, etc.
Trying to control 150 wires' worth of PWM is not the best approach here. You need smart pixels, which come in a wide range of types. They will communicate down a single chain of wires using a serial communication protocol. You can actually just buy premade pixel strings with 25 or 50 pixels on a wire, spaced 4" apart. Look for WS2801, WS2811, etc. I also sell LED stuff like the ShiftBrite
which is more modular as you chain them together with pluggable cables. The WS2811 strips are also really great because they are really cheap and you can cut them up and rewire as needed.