Modern era Legion of Super Heroes reads that I recommend:
-Legion Lost by Dan Abnett and Andy Lanning. A twelve issue miniseries.
-The Legion, by the above creative team.
-Issues 37-50 of the LOSH ongoing that began in 2004. Written by Jim Shooter and alot of fun.
-The pre-New 52 volume of LOSH begun in 2010 and written Paul Levitz (anything Legion by Levitz is gold IMO)
-The Legion Academy arc of Adventure Comics (issues 523-529) by Levitz and Phil Jimenez
-Legion: Secret Origin by Levitz and Chris Batista. A modern retelling of the Legion’s origin.
Outside of comics, I’d also recommend the New Kids In Town episode of STAS. It’s one of the show’s best and it was the first time Legion characters had been seen in animation.
Hope these are of assistance =)