Ubuntu 11.04 Natty will use Linux Kernel 2.6.38 as its default kernel. And if you want to try this kernel & the latest 2.6.37 in Ubuntu 10.04 LTS, you can install it from this PPA.

Edgy (6.10) through to Gutsy (7.10):  

sudo apt-get install linux-kernel-devel fakeroot kernel-wedge build-essential makedumpfile

Hardy (8.04)

sudo apt-get install linux-kernel-devel fakeroot kernel-wedge build-essential

Intrepid (8.10), through to Karmic (9.10)

sudo apt-get install fakeroot kernel-wedge build-essential makedumpfile kernel-package

 Ps:not exist in Intrepid, Jaunty, or any newer release

sudo apt-get build-dep linux

will also install the git-core package

Lucid (10.04):

sudo apt-get install fakeroot build-essential crash kexec-tools makedumpfile kernel-wedge
sudo apt-get build-dep linux
sudo apt-get install git-core libncurses5 libncurses5-dev libelf-dev asciidoc binutils-dev

The git repository does not include necessary control files, so you must build them by: 

Use git (detailed instructions on it can be found in the Kernel Git Guide -

 This is for users who always want to stay in sync with the latest Ubuntu kernel source. 
 

The git repository does not include necessary control files, so you must build them by:  

fakeroot debian/rules clean