Q. I try to netboot, but all I get is a flashing globe icon.
A. Even with the latest version of NetBoot (2.0.2 as of this writing), the Mac OS 9 system folder on "NetBoot HD.img" needs to be updated with Ethernet Update 2.0. Note that this is a Catch-22: you will need to boot the image (via NetBoot) in order to install the update, so you'll need to find a computer that netboots properly and use NetBoot Desktop Admin to install the update on the disk image permanently.
A.
KBase Document 120066: Apple Ethernet Update 2.0: Information and Download
Q. Does NetBoot support booting Mac OS X over the network?
A. Yes.