The easiest and most bandwidth-friendly way, if you expect to do this more than once, would be to clone the kernel's git repository and check out the version you want based on its tag. It's probably best to clone thelinux-stable repo, since that will include tags for all of the stable releases:
git clone git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
cd linux
git checkout v2.6.36.2To later switch to another version, it's easy:
git checkout v3.5.2
To update your repository to include all of the latest tags and commits:
git fetch
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If you do not want to download whole kernel commit history (which is well above 1 GiB), you can download only such part of the kernel Git repo that leads to your desired branch. E.g. to locally checkout the Ubuntu kernel in version 4.5, you'd do:
git clone --depth 1 --single-branch --branch v4.5 git://git.launchpad.net/~ubuntu-kernel-test/ubuntu/+source/linux/+git/mainline-crackThis way, the clone is about 150 MiB.