I have noticed over the past couple of months three different results while checking our sites backward links. Originally we had an extensive and "mostly accurate" set of links. We also had good positioning under the search phrases we wanted. A couple of months ago these results changed. We were left with only 4 other sites linking to us. A couple of those links were from pages that no longer exist! Our site is now a PR 4 and our positioning has slipped wahy back to the 50's. I know for a fact that we have many relevant and high quality links to our site. Is there any way to report these kind of discrepencies to Google?