Was looking around Otte NY, and found this See by Chloe dress, almost identical to the dress I didn't buy, for US$400 :/ Admittedly, the back is a sexier deep V, but I think the Warehouse dress was a much prettier green - and of course it was far more affordable. I think I'll go there today and see if they still have it. Fingers very very tightly crossed!
Also, here's a shoe TF found that looks quite similar to Katie Holmes' cute red flats. Dru patent leather flats in yumi red, and indeed they are quite yummy. Almost as yummy as Katie's, and at $104 probably a lot more affordable than whatever she's wearing.
Nevertheless, continue to let me know if you find shoe similar to hers or somehow manage to get your hands on the holy grail itself -- mary-jane ballet flats are hothotHOT.