OK
Some of these are spanish, someone might find them useful:
Twitter:
conexionionversa, chemaalonso, reversemode, owasp, xylit0l, invisig0th, ivanlef0u, 48bits, hackingexposed, vxheavens, kaepora, rogunix, 0xroot, aramosf, securityshell, anapnea, lulzsec, secbydefault.
Webs:
foro.elhacker.net
0x3a.com.ar
diosdelared.com
And some more that I will post when I remember them