Anyone interested in Budd Root's work who isn't already familiar with it, he began CAVEWOMAN in 1994-1995 as a 6-issue series. His art from 1994-2001 has more of an early John Byrne look to it.
The other series in order are CAVEWOMAN: RAIN 1-8 (1996-1997) CAVEWOMAN COLOR SPECIAL 1 (Nov 1999, only 12 pages)
After that, Budd Root's art started to change. He was hanging out with Dave Stevens, and whether on his own or because of
Stevens' influence, his art began to evolve in a beautiful way.
And it was about the time Budd Root started improving his art that he began CAVEWOMAN: PANGAEAN SEA. If you were to begin reading CAVEWOMAN, I'd skip the earlier stuff and go right to this series. At this point, 11 of 12 issues have been released, and he's taking his sweet time producing the last one. Once you've seen this run, then I think you can go back and enjoy the earlier issues, and how Root evolved up to this point. Also showing Root at his peak are the shorter nudity-laden CAVEWOMAN:JUNGLE TALES 1-3, and CAVEWOMAN: BEAUTIES & BEASTS 1 and 2.
The first 6-issue 1994 series was a few years ago re-released in a new "director's cut" type reprint series, as CAVEWOMAN: RELOADED 1-6, where Root added about 10 pages of new scenes to each issue. I guess this is a good starting point too. But while it starts you at the beginning and has some nice new pages, it's kind of a warts-and-all package that forces you to read his cruder early work that is far below what he's doing now.
Aside from that, you have CAVEWOMAN:PREHISTORIC PIN-UPS 1-7 (or so) that aren't stories by Root, but 32 pages each of pin-up pages and convention sketches. I think he stopped these, and now just does annual convention books.
The other Cavewoman books are all by other artists, and may have Bud Root covers, but are either by Devon Massey (most of them) or Paul Renaud (the last 5 years or so of new CAVEWOMAN titles). And, like Mignola's farming out HELLBOY, I've mostly hated any CAVEWOMAN titles that Root didn't write and draw himself.
The one exception was Devon Massey's first effort, in CAVEWOMAN: ONE-SHOT. But his art got much looser and out of proportion after that.
You can probably find the cheapest price on these from the source, at http://www.amryl.com