Import simply does a one time creation of the list. If you want an
Excel sheet linked to the list  for making future updates, you'll need to
export a new spreadsheet  from the list and make your updates there.

Or, if you have Office 2003, you can use the Export and Link to Excel
option that's available from the Datasheet View of a list  (in a task
pane that is hidden by default on the right hand-side of the datasheet!)

Once a list is linked you can use the List/Synchronize option in Excel
2003...

I have a very simple query let me know if you folks could help me..

I add a office  spreadsheet webpart  to my homepage of the sharepoint  site.
The spreadsheet  has contents through 100 + rows. No, I want to freeze the cells
till the first 5 rows  as when I scroll through the rows down the top 5 rows
[with titles/descriptions] should be visible.

Is this possible ?? I tried the tools available but doesnt help. Appreciate any
suggestion.