I got my samples from carb.com, and i have kevlar, carbon, and glass composed fabrics. What are the main differences (besides color).
The difference is in strength and material. Generally fibreglass is the easiest to use because it’s light and you don’t have to worry about the weave lining up straight. Next up is carbon and kevlar which works the same way but is stronger than glass. Kevlar is mainly used for the coloring effect.
so carbon fiber is the hardest to use?
Of the 3, yes.
I feel the kevlar is harder to work with, it just doesnt flex like all CF. Also Kevlar is much harder to cut then CF so sharpen your shears.
I wish I could remember where, but I saw a site selling shears for cutting Kevlar (the material, not the bf.c moderator 
). If you look on eBay for the carbon fiber materials kit (comes with resin, hardener, some fabric, etc), their online store (not eBay store) has the Kevlar shears.
how much were the samples? I am trying to get started as well, but I can’t figure out the pricing tables.
I’ve seen starter kits that go for anywhere from $50 - $100 range.
The shears for cutting kelvar are on that aircraft site posted in the material buyers thread. I remember them being there when I was browsing.