StockSubmitter has full support (including automatic submission) for the following agencies:
123rf
Alamy
BigStockPhoto
CanStockPhoto
ClipCanvas
CreStock
CutCaster
DepositPhotos
Dreamstime
EPS
Fotolia
GraphicRiver
iStock
Lori
PhotoDune
Pixta
Pond5
RevoStock
Shutterstock
VectorStock
Veer
VideoHive