Yep, it's all tablet and photoshop drawings.
As for clean lines, well, you might be asking the wrong person that (
) but for me and my own drawing style, I have thick black lines to work with, so after I've drawn them and start to lean them up, I use the eraser tool and just kinda whittle away at the lines, fixing and bumps or bad edges. I also use a lot of layers on top of layers so when I get to cleaning I don't erase lines I don't want to.
Oh, and to give the illusion of clean looking lines draw at a much higher resolution then normal, like I draw at 1500x2000, then crop the image after I've drawn it and THEN half the size before posting it on the forums. Looks nicer and gives the illusion I've actually gotten better at it (I haven't
).