Both Alpha and Omega's theme descriptions say:
"This theme should not be used directly, instead choose one of the Omega or Alpha starterkits."
However, if you have no idea what the heck a 'Omega or Alpha starterkit' is, you are pretty stuck. :)
Seems like the word 'starterkit' should probably link to README.txt? Or maybe to http://omega.developmentgeeks.com/documentation/subthemes ?