but maybe I wasn't clear on the help I needed. I need help putting together the hardware necessary to control an LED Matrix with a PC.
Well to start off with you need to be more precise in your description of what you want to build. The word matrix is too general a word used by itself. A single row of 4 leds could be called a one dimension matrix comprised of four led elements. A 8X8 (64 leds) would be called a 2 dimensional matrix. A LED 5X5X5 cube would be called a three dimensional matrix comprised of 125 leds.
You did mention wanting to use RGB leds, That in itself adds another "dimension" to your 'thingee', as it no longer is just a choice of that a given led is either off or on, but rather off or one of three primary colors, or even off or one of seven color combinations.
All the details of hardware requirements, components, wiring methods, and programming methods to be used, start with a good accurate description on what you are trying to build.