detectors of and the need for same. and, if the detector goes off i
should then....?

open the windows, close the cabin vent and shut off cabin heat so that no
air from the engine area gets routed into the cabin. get it on the ground
asap.

whats the deal with o2. it doesn't really seem all that expensive and
it seems like it should be the pilots drug of choice. wrong(again)?

the O2 itself isn't expensive, but a small bare-bones o2 bottle with
regulator and cannula will run about $500. which is worth it if you need and
use it frequently, but kind of a luxury item if you don't, just be aware of
situations where hypoxia is possible and avoid them.