How do I break up with a guy...who I also work with?

Yeah, yeah I know, mistake # 1 was dating someone I work with. It hasn't been too long, less than 2 months. There's just no connection, nothing in common. I also feel he is stalking me, which is annoying. I don't work directly with him, but would have to communicate information to him on a daily basis face to face. Okay, so don't chastise me for dating someone I work with. Just help me get away from him tactfully.... No one at work knows we've been seeing each other.