I'm not sure how it is where you are from, but here in Norway, it's considered polite and correct to look someone in the eyes when you talk to them. This is especially true if you're in a job interview or meeting your father-in-law for the first time. If you don't dare look them in the eyes, chances are fairly good that you won't get the job/girl. Anyway, a good trick is to just look at their forehead instead. To them it looks just like you are looking them straight in the eye, but you really aren't. Also, I don't think you should stare all the time, it's ok to not look at a person all the time, but when you are looking at them, look them in the eyes.