here is Rose Berenbaum’s blog- Real Baking with Rose Levy Beranbaum
maybe the recipes are here?
ooh wait, found 'em! God bless the interweb! 
http://www.recipezaar.com/yellow-butter-cake-by-rose-levy-beranbaum-407413
yellow butter cake
http://www.recipezaar.com/Perfect-Chocolate-Butter-Cake-29976
chocolate butter cake