Hello

1) Can anybody tell me if i put some data into 1-3rd normal form,and i want to then use ER modelling, do i go back to the beginning of the raw data, or "er" the normal forms?

2) what are the similariites and differences between the 2 approaches, that i should see, providing i get it right

i'm really stuck on this so i hope somebody out there can help me

ERs and Normalization? Well, you're not necessarily comparing Apples to Oranges here, but its at least Oranges to Tangerines...
Regardless, a 3rd normal form design should be easy to mock up in an ER diagram.

Generally people use ER modelling to produce 3NF designs, I'm not sure I understand the question...