I'm only missing Volumes 41 and 42... or 25 and 26 as Viz would have me call them. But I plan to soon get them. I'm a bit disappointed with Viz's translations and censorship lately. Hercule?! What the crap?! Oh, an Ingo, if you need any more proof that there really is no DBZ manga, just look at almost any of the cover images. Toriyama almost always includes the volume number, sometimes subtlely, sometimes overtly (No. 40, I'm looking in your direction!) in that image, almost as if he knew someone would come along and screw around with his numbering. Plus, no one's gotten this specific, but the DBZ part of the anime doesn't actually come at a perfect division between volumes of the manga. So Viz cut off the first two chapters of Volume 17 and later tacked them onto the end of Volume 16. That's why "DBZ Volume 1" is so short, while DB Volume 16 is so long.

And, yes, I need more shelf space!

EDIT: And, ric, I've actually heard (but not seen) that there is a DBGT manga, but, of course, it's based on the anime rather than the other way around like with the rest of DB. Maybe it's simply an animanga, but I have heard it exists.

EDIT AGAIN: Also to ric. You're just a bit off the mark by saying that Toriyama had no involvement with GT. I don't consider it canon myself (and I've not watched a lot of it either), but Toriyama did do the character designs (including GT-exclusive characters), and he did help set up the original premise of the show. But his participation was extremely limited. He also designed a lot of characters for the movies and TV specials.