I don't have the courage to use a tripod in public. It took me a while to start using the SLR too, I was afraid of people looking at me (I'm shy, if you can't tell)

Cameras are generally quite fast in most well-lit situations so your shakiness doesn't affect it at all. In other situations, I've noticed other photographers will start leaning against things to get steady, so I do the same. For example, they'll press the camera back against a lamppost and take the shot, or they'll lean their elbow with all weight against a stone block, or even use knees, bags, friends, books, cadavers, cigarette cases, etc.

What I'm saying is that hand-shake is not a big deal because SLRs give you lots of control. P&S cameras can be a little difficult that way though.