Referrers stats

I openly admit it when it comes down to referrers stats and .htaccess, that I have no idea what is going on.

I was just looking through my server stats and I have things like,

85133:shadows.os42.com/
27140:www.3arabawys.com/
25480:www.os42.com/
16660:www.myspace.com/
6642: images.google.com/
3024:www.voetbalprimeur.nl/
2852:images.google.nl/
1945:images.google.co.uk/
1795:krustystills.blogspot.com/
1653:images.search.yahoo.com/
1298:www.livejournal.com/
1130:www.namco.com/
1120:ruthlessreviews.com/
1005:images.google.ca/

Now most of these sites have absolutely nothing to do with me and no visible links that back to me that I can see, so what is going on? Why do they show as referrers. I gather it is some form of spam but what do I need to do to get rid of it or is it a non-issue?

Sorry for my ignorance.