I just happen to be looking at this drawing (I was amazed that this is done with a mouse!) and saw your comment.
Wacoms are awesome and cheap! Mine was only $89 and it works wonderfully!
I just started using it in September and then went to fully digital about 6 weeks ago
It took a bit of getting used to, but it's super easy now. I don't even think about it!
Hmmm, I went to look it up online for you and it's not on the Wacom sight anymore,
but I have Wacom Capture. It works for everything for me and was really cheap when it was full price.
Maybe Amazon or Ebay might have it?
It'll be hard and frustrating at first, coloring comes easiest, then sketching, then the line art comes later.