Dilemma&Complaint...all about men

I need advice desperately, I got to know this guy who sounded really great (fashion photographer - straight!) but then I saw his pic and knew he definitely wasn't the one. So don't know what to do - is it better to ignore him totally, tell the truth or tell a white lie aka lame excuse. So difficult I hate being not nice to people.
Also I'm trying to figure out why when you say no to sex with a guy (but not like no=in your dreams, more like no=i'm hard to get) he immediately becomes so passive agressive, starts being mean, nasty, accusing you and makes you the bad one. What's wrong with you guys - that's not very likely to get you laid,just wait for another date (UPDATE: I said wait, not give up hoping! I just hate it when you never hear from the guy again if you don't sleep with him immediately.urgh!!!)