'What do I take a picture of?

I often look in magazines and pictures on walls and think..'Wow what a pretty picture'. Now that I have started photography I try to take those pictures. The one thing I have noticed when just out and about is...'What do I take a picture of?' I often draw a big blank in my mind. This one question has drove me to try out landscape and urbanscape photography.... Tell me what you think! :o)