Ditto to Malcolm's, Liz's and Mark's comments. It helps a lot to have someone show you around the sky. It also helps to have a Telrad to point the dob in the right direction - very hard to do just by lining up the tube. Good star charts help. I also found as a newbie that the
Atlas of the Southern Night Sky was a good combination of charts with suggested targets and images of the targets so that you know what you're looking for.
Wikisky and the
Digitised Sky Survey are also good ways of finding images that will look a bit like what you see through the scope. (And
Clouds of Magellan of course if you're after objects in the Magellanic Clouds.)