When the tree is that close to the other property, there really isn't anything you can do to contain the needles, other than helping clean them up. You could trim the branches (if they ""tore"" the branches,then I would definitely recommend this...cut back cleanly to a joint or the trunk so the bark can seal the wound). Also, there are gutter guards available at hardware and home improvement stores.
By the way, pine needles make an excellent mulch, particularly for pine trees, azaleas, blueberries and other acid-loving plants. Some nurseries actually SELL the stuff!
Luke Miller, editor
Garden Ideas & Outdoor Living magazine