I am trying to install the Android API level 13 and 15, but the SDK Platform is not appearing in the SDK Manager.. I tried updating the ADT but no updates were found, I assume at first that it’s up to date but when I open Android in the Preferences menu, it says that the SDK requires ADT 20 and my current is 16. I’m using Eclipse Indigo, any work arounds? Thanks.
btw, here’s the screenshot of my SDK Manager:

and here is the Android Preference:

I solved it, the problem was the SDK Tool is outdated so I have to update it first before I was able to finally see the Android 13 and 15.. Don’t know why, but it works. thanks for the answers anyway 🙂