You should use the YaST software management module l and search for "kernel'. You will find the -devel files there for your kernel. Unfortuantely even if you do install the headers (you may have done so already) VMware won't find them even though they are there. If you lookk at the directory in Dolphin you will see .h files but they will be greyed out. I haven't found a solution for this - it seems to be a kernel problem although VirtualBox has no problem compiling.
Good luck