quick walkthrough here:
http://www.get-virtual.info/2011/01/26/extending-a-windows-c-dell-extpart/
you have 3 further options though
1) you could use VMware converter to conver tand resize the machine disks (pretty easy)
2) attach the disk to a second VM and resize on this host - then re-attach to the original vm
3) Try vmkfstools
Good luck