Guys please help me out!?

I used to work on the second floor at my job in which I would see this guy normally on my way from and to lunch. I never said hi or anything. One day I hit his car while opening my door (not a big deal) and then he smiled and said I owed him coffee. I then did this ugly face and said no. Now, let me back up a little bit and say that I am 23 years old, still a virgin and scared to talk to guys (I have never kissed or dated a guy too)... Then the next day, while just thinking how stupid I reacted I went to Starbucks and told someone to give him coffee that I bought. So that was seven months ago and then recently in February I move to the 3rd floor where he works at now because I am no longer full time but part time and see him Thursdays and Fridays. Now everytime I work, he says hi to me and comes to my cubicle. Also, it is not like it is close to where I work at compared to where he is. Honestly, I don't know how to talk to him and have developed a big crush for him. He is also a manager and I am a customer service representative. I am very attractive too but a bit on the chunky side and he is very fit. What should I do? Does this guy like me or not? Also, I am about to leave the company for a better paying job and am wondering what should I do or say to him? Please help me out! I really like this guy.