Is that how this goes? Well...
Favorite writers: I'm almost sure Gaiman goes here, though I can't say for Sandman as my experience of that is nearly nil, but his other works, including for example Death and Marvel: 1604 were nothing short of great. Another good one is of course Morrison, then there's Miller(Sin City, The Dark Knight Returns) and Mignola(Hellboy). I see no point adding a few finnish ones, as their names will say nothing to you. Mainly underground and barbarian stuff. Somebody might have seen Pauli Hiltunen's Elric and Conan illustrations, but I rather doubt that.
As for fav artists; I can't say for sure. It's a mood thing, really. Sometimes Leinil Yu's(lots of Marvel stuff) incredibly sharp line work charms me to no end and then other times Zulli's(Sandman, TMNT, etc) scribbles look grand. But there's one illustrator whom never seems to fail, and that's Adam Kubert(Bat, Origin, 1604). Granted; he usually has high end aftercoloring to really get the images to shine, but I love his work all the same. Some manga is also neato, like Hellsing(sometimes looks like retched blood though:D) for instance, but I can't really name any artists.
Hem hem... I like Ultimate X-Men. There. I wrote it. Now you can laugh.
Edit: Who's the one drawing LoEG? I've been trying to get to the comic for ages, but I just can't get myself to like the art.