Where can I find resources for subnetting in binary?

I need to learn to subnet for the Network+ exam. I read mike myers all in one guide but the process seems to break down at the end when I need to ign IP ranges to the network ID;s. to be honest the whole thing is blurry. I emailed the author and after consulting with the subnet dude, he sent me a web link from Cisco explaining how you can indeed use all ones or zero's for the subnets. Again, in the dark. Can you use a calculator of some sort on the exam? Man, I really need help here... Does anyone know of a full list of any or all misprints in his "all in one" exam guide 2009?