Using http://www.backlinkwatch.com/ I have found a huge number of crappy sites linking to my corporate site. Examples. http://finance.ridingfieldssquare.co.uk/4/ http://finance.lavenderwalk.org.uk/100/ http://finance.robertwoodavenue.co.uk/28/ http://finance.ridingfieldssquare.co.uk/3/ http://finance.richmondway.co.uk/21/ http://finance.havengarth.me.uk/7/ These are relatively new. These are not ones for which we have paid. (scratch that - we don't pay for any...) How can I find out who owns this. We have had a relationship with a company in the past who might be up for malicious linking in order to affect rank.
If you're really keen, do a whois lookup. These show a name and a statement that he's opted not to show his address - but his registrar, and hosting company will be able to provide info if you have a legitimate reason. Nevertheless, I don't see why you're so concerned - none of the search engines penalize you for these kind of backlinks. They are concerned about a) The number of GOOD backlinks you have (you could have zillions of other backlinks but it doesn't matter) b) The quality of your website c) YOUR outgoing links. As long as you haven't linked to these sites, you shouldn't have a problem. Otherwise - with every spammer having links to yahoo or google or other portals, those should have lost PR long ago
If you have ever submitted an article to an article directory, then you can expect scads of odd looking backlinks to appear as your resource information becomes active. For the most part, this shouldn't be a problem and you may actually see some of the links get ranked.