Inserting new line with formula's already added

I have seen alot of responces for this on other threads and forums but none seem to do what I need:

I would like a command button to add a new line into a spreadhseet and continue the formulae from the previous line (i.e. all link into a total line)

But...
I have locked cells in the exsisting rows which need to stay locked in the new rows
and the spreadhseet is split into different sections which all need lines added and if possible I would prefer only to have one button.

Does anyone know of a way I can do this??

Thanks for your help in advance
Ben