No making-of docu?!
Dunno about the full set, but I got the Aliens DVD (not Blu-Ray) a couple of years back, and it had some great "making-of" stuff on there. Essential viewing in these days of green-screen and CGI, when the powerlifter-vs-queen fight is *really* being staged between 10-foot-tall constructions, with Sigourney Weaver inside, and all controlled by a couple of dozen experts with hydraulics, control lines and sheer brute force. Also for the sets, particularly the loading bay, which again these days would be inserted in CGI but back then were actually built. The actors' training segment was also pretty fun, talking about the guy playing Apone (an ex-sergeant) basically putting them through boot camp so they'd look and behave like actual soldiers.
If they've deleted that from the Blu-Ray, I recommend not buying it.