Thanks for ideas and advice, guys!
I found a couple of great free brushes on www.kylebrush.com that seem to be really nice. I guess you are right — it's all going to take some time to get used to. I also prefer drawing on paper, but I feel like in order to operate in some of the fields I want to break into, I need to become proficient with the tablet.
Here's my latest drawing with the new brushes - critiques needed!