M.O.P.
Nas
The Roots
Beanie Siegal (sometimes)
Gang Starr
The Diggin' In The Crates Crew (Big L., Fat Joe, Big Pun, Diamond D., Lord Finesse, Showbiz & A.G., O.C., etc.)
Redman (sometimes)
Generally, you can't go wrong with most East Coast Rap that came out between (roughly) 1986 up to about 1996 or so, IMHO. New York back then still cared about making hard street music that represented NYC, but that other cities could enjoy, too. My favorites from that period include EPMD, Eric B. and Rakim, Public Enemy, BDP, Slick Rick, A Tribe Called Quest (first three CDs), Pete Rock and CL Smooth, Kool G. Rap, Brand Nubian, and of course the original Wu-Tang Clan (1993-96).
PEACE!