Need C header files for Kubuntu Kernel

I'm trying to install VMWareTools on VMWare Server but during the install I get the message:

Trying to find a suitable vmhgfs module for your running kernel.

None of the pre-built vmhgfs modules for VMware Tools is suitable for your
running kernel. Do you want this program to try to build the vmhgfs module for
your system (you need to have a C compiler installed on your system)? [yes] y

Using compiler "/usr/bin/gcc". Use environment variable CC to override.

What is the location of the directory of C header files that match your running
kernel? [/usr/src/linux/include]

The path "/usr/src/linux/include" is not an existing directory.

So then I checked my kernel version:

jreed@jreedkubutudesktop:~$ uname -a
Linux jreedkubutudesktop 2.6.15-26-386 #1 PREEMPT Thu Aug 3 02:52:00 UTC 2006 i686 GNU/Linux

Next I tried to download the headers:

jreed@jreedkubutudesktop:~$ sudo apt-get install linux-headers-2.6.12-26
Password:
Reading package lists... Done
Building dependency tree... Done
E: Couldn't find package linux-headers-2.6.12-26[/color]

Unsure where to go from here??

Thanks that's just what I needed to know - it worked great! I really appreciate your help.

What errors are you getting?

try this, it's what i use...

sudo apt-get install linux-headers-$(uname -r)