Creating complex tables in views in Drupal 7
The Views UI supports this.

Once you have your View configured, click on the "Settings" link in the Format section. You will then see a table that allow you to choose which column each field should appear in. See screenshot below. In this example, if you wanted the Author uid and Nid fields to appear in the same column, you would just select Author uid from the select list next to Nid (or vice versa).