OK Jason, good to know its a Dob!
I assume you mean M42 not M47. M42 is the Orion Nebula, M47 is an Open Cluster in Puppis. M47 will be visible tonight but will probably be best after midnight. It is nearly able to be found naked eye if your skies are dark enough.
To research a nights observing there are lots of ways. There are a nimber of free programs such as Stellarium that can tell you what constellations will be visible and some of the bright objects available. If you prefer books, Collins Stars and Planets is a great guide to a large number of easly seen objects. It can be found here
http://www.bintel.com.au/Accessories...4/catmenu.aspx
Best advice is see if there are any clubs or groups in your area so you can see what other observers do.
Malcolm