My Son (now 10) has always suffered with eczema. When he was a baby his cheeks used to bleed, and his skin always looked so sore.
I have always used the Tescos non bio washing tablets, and the Tescos sensitive conditioner. If I change it at all (once I got same brand, but different scent) he flares up terribly. You have to experiment though, as the same things don't suit everybody.
My Son was seen by a consultant as a baby, and prescribed the 'wet wrap technique'. That works really well, and I still do it now from time to time if he has a bad flare up.
I always used hydrocortisone on his face, and plenty of emulsiying ointment too. On his body, eumovate ointment and plenty of emulsifying ointment (and bandages if he needs them).
I want you to know though, that even though his face was really bad as a baby, he grew out of it very quickly. By the time he was 10 months old, he never got it on his face (and never has since). Now, he just has dry skin, and his ankles and hands crack sometimes, but it really isn't that bad now.
People used to tell me it would be so much better when he was at school age, and I couldn't believe them, because it looked so awful, but they were right.
I hope you find the right treatment for your DD, I know how distressing it can be for both parent and child. As a Mum, you don't want your child to be uncomfortable, it's hard to deal with.
I must say as well, I had two other children, and neither have eczema at all (just my middle son). I guess he was the unlucky one.
Good luck.