this has been one of the hardest applications for me to learn.
i watched the 3DBuzz Zbrush tutorials & the Pixologic Zbrush tutorials. i was still mystified, but it still seemed like a good program.
at this point i’d say it’s a GREAT program, but one of the wierdest interfaces i’ve ever encountered, as if it was designed by Vulcans or alien beings or something.
Eric Keller’s tutorial at Lynda.com helped me get it sorted out.
http://www.lynda.com/home/DisplayCourse.aspx?lpk2=642
also, digital tutors has several Zbrush tutorials.
Intro
http://www.digitaltutors.com/store/product.php?productid=3108&cat=98&page=1
character & scene development
http://www.digitaltutors.com/store/product.php?productid=3623&cat=98&page=1
both of those have a section on displacement maps.
extracting displacement maps & understanding the details of the UV’s seems like a really important & powerful detail of Zbrush.
i downloaded
http://www.crazybump.com/
for converting Zbrush normal bumps to disp. bumps, that is a cool program.
once i understand it better i’ll go back to the 3D Buzz tutorials. Zak goes through a work session that lasts several hours where he creates detail in Zbrush & Photoshop and then brings it into Maya, to create a very detailed but fairly low-res Goblin character. worth learning but the first time i watched it at least half of it went over my head.