what does it matter if he looks at porn or jacks off? lots of guys do it, hell lots of girls do it. -I- do it. If hes neglecting you in a relationship then thats his problem and shouldnt be attributed to porn or how often he masturbates. dont get defensive and dont attack him. swallow your anger and have a mature, adult conversation with him.
also you should consider that another part of being in a relationship is free will. do not tell him what he is or isnt allowed to do. you wouldnt like it if he did it to you.
also, dont stalk him on the internet and respect his privacy.. dont read his txt msgs or listen to his voicemail.. thats private and personal and really isnt your place to be looking or listening.. respect him and he will do the same to you..
good luck