The first link doesn't really help, I've been working with this one of the past hour or so.
http://www.bcae1.com/wire.htm
So using the calculations on that page, I have:
Resistance:
R = 1 / 1.26 ^ (difference between 8awg and 10awg)
R = 1 / 1.26 ^ 2
R = 1 / 1.586
R = .629881582
Amps:
I = E / R
I = 12 / .629881582
I = 19.051200008
Is this right? Hey, I'm using the resources you're giving me and trying. If someone explained the rest, it wouldn't be spoon feeding. My next question is, "Do I now get the amp rating for my speaker amp, add it to the 19 for my sub amp and use that to see if it'd draw too much power on the single 8 gauge going from the distribution block to the battery?"