in Alfresco 3.0 (an now outdated version) the SDK was shipped with the downloadable installer / package. Thus there is no download site that currently provides it as it has been outdated for some years. As far as I can see, the wiki only provides a <a href="https://wiki.alfresco.com/wiki/Community_file_list_3.4.a">Community file list for 3.4 (including SDK)</a> but not for 3.0.
