my sugestion is:
click on the row # below you entered data ( the whole row should be
highlighted )
for example if your data entry comes up till row 100 you should highlight
the row 101
hit end key and the hold shift and hit down arrow key ( all rows in the
sheet should be highlighted except the area you entered your data )
right click on the highlighted area and choos format cells and then go to
protection tab and uncheck the locked checkbox
go to: Tools>Protection>protect sheet and creat a password and then click ok
every time you entered new data you have to unprotect your sheet and just
highlight your data area and right click on them and choos format cells and
go to protection tab and make the locked check box checked and then protect
your sheet again.
Thanks,