You can get all these from here, but they do not index there files very well so here is a list of what they have (I only list the last version released)
Alot of these have had very recent updates in the last 2 years 2010-2011
For systems that have more than one emu they are listed by release date, newest last oldest first
Other SystemsAPPLESpoiler warning:ATARISpoiler warning:COMMODORESpoiler warning:NECSpoiler warning:Neo-GeoSpoiler warning:NINTENDOSpoiler warning:SEGASpoiler warning:SONYSpoiler warning:Other StuffsSpoiler warning:ARCADESpoiler warning:Spoiler warning: