Well, If you're a techie type of guy (like me) and not the physical drawer (using free-hand like pen to pad) I suggest you try going into vectoring...
However, free-hand drawing/using a pad tends to be more easier contrary vectoring. For it is quite different than drawing lines into something great... Vectoring requires you make shapes that you need, manipulate them, and THEN make something great :3
So, if you're interested into vectoring, I suggest incscape/ponyscape, or gimp. (you can free draw like others in these but it's quite hard without a tablet AND they don't really have good brushes to use... but, they're free softwares!)
Otherwise, I suggest you start practicing with traditional pencil-paper, save money for SAI and a tablet, and have fun!