yes, you definately need to get some grays. I use the cool gray set, but some people prefer warm greys, just a personal preference really. I never use the prisma blender, that thing sucks, you just have to practice blending your colors. If you want to add white in a colored area, use a white colored pencil to add it in, after you have applied the color. If you want something even brighter, you can use goache, or you can just do it the easy way and scan it into photoshop and burn it with the lollipop tool. I suggest the book Creative Markering Techniques, it will teach you some basics, and give you some good examples for different surfaces. Also, I wouldn't waste my money on those big prisma sets, all you need is a few colors, but you should have a full set of grays...
ooooo
from now until infinity let icons be by-gones...
