So far this month I have had over 600 error code 404 for my site. Primarily from the two url's and referers listed below. I am at a complete loss as to where the url's came from or why they are on my site or what it means.

Please help.

URL 404 Error Hits
/images/spacer.gif 301 errors
/catalog/manufacturer.asp 281 errors


Referers
http://www.theoutdoorsportsshop.com/firearms.htm
http://www.theoutdoorsportsshop.com/firearms.htm