Do you guys find it difficult to talk to girls?

I think the best way to talk to girls and I suppose, gain confidence in general, is to basically fake it until you make it. Even if inside you're freaking out or are insecure, just portray that confidence aura (good posture, hands not in front covering you, etc.) and just go along with the flow.

Sometimes the flow Stop in the middle of nowhere

Yeah but there's a difference between a natural lull in the conversation and tense men talk panicking. Go for the former :p

Xueli has a good point. You convey so much through body language. Don't let your hands fidget. Also it's ok to ask the other person if they have something they want to talk about. This next one is a little sneaky but you can ask them to tell you more about themselves. One of two things will happen: they go on about a facet of their life and you may find you have something else in common, or they could fumble and not think of anything else to say and you can both share in the awkward but cute moment.