I want to take a +12V power supply and duplicate it creating
1- +12v out 1- -12v out
easier said than done?
What you need is a switching inverting regulator capable of dealing with +12V at its input and supplying enough current for your application.
However, keep in mind you'll require additional components and that laying out a good PCB may be critical! It will be something like this (the image shows +5V to -5V but the device is capable of +12V to -12V as well):
Some devices that you may find useful:
You may also like to consider a commercially available pre-assembled board.
You can use something like TPS65131-Q1, a positive and negative output DC-DC converter. Below is an application schematic diagram:
Note that this converter can take only 2.7--5.5V on its input while having dual output up to 15V and down to -15V. For this reason you would have to:
1) Choose a more suitable DC-DC converter that has a dual positive/negative output.
2) Step down potential difference from the output of your power supply (+12V). You can use a linear voltage regulator or a simple buck converter. It depends on how much current the load needs. Also, it would be good if this buck converter wouldn't switch at the same frequency as TPS65131-Q1 (minimum 1.25Mhz).