you have now entered a world of pain and expense, but also one of lots of fun

If the book was Understanding Exposure by Bryan Peterson i too recommend it, tis a good read.
A good way to learn is to just play, understanding all the functions on your camera is also handy but that'll come with time.
Get yourself a flickr account and have a nose about, find someone else's photo that you like then try and imitate it, if you can't figure it out ask the photographer, most people are happy to share how they did it, if not, i'm sure some of the resident DDN experts will be able to help you out.
Since owning my DSLR i've progressed through several "styles" of photography (evident from my flickr account)
Started with HDR as i was a fan of StuckInCustoms - moved away from this recently unless the weather is completly pants.
Long Night exposures, after buying my tripod this seemed like the logical way to play, it is good fun, easy and you can get some great results
Long exposure day shots - generally i only take these when confronted with a waterfall - all you need is a ND filter and a tripod.
Most of my shots are seascape or landscape as that is what i am surrounded by, but i would like to get into people and objects, but that opens a whole new pain of lighting!