help with ohms

Start here, read through chapters 2 to 12.  By the time you get to 12, which is about ohm's law, you will be able to understand it.  Read as much of the site as you can, because you'll learn at every page.  There are other tutorials and help on the web besides that, but it is great to get you started because of its easy-to-read style.

Ohm's Law can take months to fully grasp (I know!), as it describes all the forces, and their relationships, that  you will deal with in installing and using a car sound system.  Quick hookup diagrams can be found here and here, and will help you get your subs up and running...but when the day comes that you grasp the principles of Ohm's Law, nobody will ever be able to bullsh*t you about anything re: car audio again.