I have a code for the heated Oxygen Sensor Bank 1, Sensor 2.
Where is this sensor located?
What is the best way to access for replacement?

Found them!! But it appears that only 2 oxygen sensors exists. One before and one after the Cat. Is this correct, only 2? Are they the same?

Purchased the before heated O2 sensor. The code is Bank 1, Sensor 2 (after cat). Can I use it as the after Cat sensor?

2 sounds right. Click on "buy parts" above and track it down - there's a wealth of information there.

I tracked down the parts from above. They show 2 bosch parts.
My question is that other than the length of the cable, are these o2 sensors the same? Can I use the one I have as the after o2 sensor?

That would be here:
http://www.boschautoparts.com/Resources/VehiclePartFinder/
If they have the same universal type, and they do, they are the same sensor with different wiring.