The tip can be found here. Basically, here is what you do:
- Create a new Writer Table with the number of columns and rows you need
- In Calc, select and copy the range of cells you want to import into Writer
- In Writer, use Paste Special below or above the Writer table (not in the table, yet). For 'Selection', choose either "Formatted text [RTF]" or "HTML (HyperText Markup Language)". This creates a temporary table.
- Select and copy the contents of the newly created (but badly formatted) temporary table.
- Paste the contents of the temporary table into the original table you created in the first step.
- Delete the temporary table.