Every paint line calls the same color something slightly different. Also, the color in the photo is going to look different on your computer monitor as opposed to someone else's. Not to mention that everyone's eyes and color perception are different, too.
Just go to the hobby store and start comparing colors. I wear glasses, so what I do is take my glasses off so my vision is blurred which will make slight shade differences blend together. That helps me narrow it down to the color ranges and tones I need to focus on.