kernel compile step 1

[jjheuring]

Could someone tell me where the <kernel source tree> is?

I did 'apt-get install kernel-package'.  Shouldn't it now be in
the /usr/src dir ? That's empty for me. I've read the various
README's at /usr/share/kernel-package and they had some other
suggestions as to where I might want to unpack the kernel but I don't
see anything where there is an executable make file.