Nuclear:
I mistakenly slowly backed into something and cracked my right rear reflector tonight. I already went to the GM parts website and located the part.
Google "GM OEM parts" and you will get the GM parts website. Then select 2010 Chevy Equinox (2011 is not up yet, and the 2011 equinox is the same), then select "rear bumper" and "rear reflectors" is under there. They cost $25.00 (part costs a dollar to make-no surprise). It also has a parts/assembly diagram.
Looks like from the drawing the reflector has tabs that hold it in place, and it pops in from the outside. I am planning on replacing mine on my own. To avoid damaging the bumper (paint), I may crack the reflector in two to get it out, then pop the new one in. I do think you can pry it out no problem.
Have you replaced yours yet? Let me know if you learned anything.