If you get the following really annoying message while trying to install the andriod SDK on ubuntu:
Stopping ADB server failed (code -1). Unable to run 'adb': Cannot run program "/home/user/android-sdk-linux/platform-tools/adb": java.io.IOException: error=2, No such file or directory. Starting ADB server failed (code -1).
It's because you're running 64bit ubuntu, and phones (and therefore the SDK) are only 32bit, if you run:
apt-get install ia32-libs
It will solve all of your problems and the SDK will install correctly.