Well, there's certainly folks here who will gladly buy all your chrome stuff if you're reasonable with asking price ... just be careful when you remove the door moldings so as not to bend them too much or else they will become useless. You can usually purchase the non chrome version of all the handles, door moldings (will have to have them painted), grille, mirror caps, on ebay for much less than the dealer sells them.
Best way to find the part numbers is to go to a dealer lot, find a black LT, write down the VIN, and go to the parts dept. to ask for the part numbers.
The rear bumper chrome is going to be a little harder because they don't make a non chrome step pad molding for the LTZ bumper. So you either have to swap for an LT bumper assy & step pad, or have the chrome strip painted or plasti-dipped.
I'm not sure how one gets the front grille surround blacked out ... there may be a black version of it, or more likely, you will also have to have that painted.
AMI All Sales make the black bowties I have on.
Hopefully this is enough to get you started ... if you need specific part numbers I'm happy to try to track them down.
And welcome to TYF.