Wood chunks. I experimented with using chips last year and didn't get much out of them.
Not sure what you mean by what type of bbq? I was smoking them in a WSM, they had a rub from penzey's spice - the one on the ribs wasn't great, the one on the chicken was pretty nice.
I added the wood by spreading a layer of charcoal on the bottom, putting the wood on top of that, and then pouring the lit charcoal on top of them both.