juan@metalero9:~$  sudo apt-cache show linux-headers
juan@metalero9:~$ sudo apt-get--cache show linux-headers
sudo: apt-get--cache: command not found
juan@metalero9:~$ apt-cache search linux-headers
linux-headers-2.6.17-10 - Header files related to Linux kernel version 2.6.17
linux-headers-2.6.17-10-386 - Linux kernel headers for version 2.6.17 on i386
linux-headers-2.6.17-10-generic - Linux kernel headers for version 2.6.17 on x86/x86_64
linux-headers-2.6.17-10-server - Linux kernel headers for version 2.6.17 on x86/x86_64
linux-headers-2.6.17-10-server-bigiron - Linux kernel headers for version 2.6.17 on BigIron Server Equipment
linux-headers-386 - Linux kernel headers on 386
linux-headers-686 - Obsoleted by: linux-headers-generic
linux-headers-generic - Generic Linux kernel headers
linux-headers-k7 - Obsoleted by: linux-headers-generic
linux-headers-server - Linux kernel headers on Server Equipment.
linux-headers-server-bigiron - Linux kernel headers on BigIron Server Equipment.
linux-source-2.6.17 - Linux kernel source for version 2.6.17 with Ubuntu patches
xen-source-2.6.16 - Linux kernel source for version 2.6.17 with Ubuntu patches
juan@metalero9:~$