Ok, I did find 2 that you were billed for insurance on, but it looks like the buyer did local pickup.
http://www.auctiva.com/sales/saledetails.aspx?tid=149600798
http://www.auctiva.com/sales/saledetails.aspx?tid=149679154
Could that be the problem? You have insurance
You do have insuranced listed as included in shipping and handling though for local pickup:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260214453120
You should probably set it to not available when you give the local pickup option and then we would not automatically purchase it for you. It is a computer though and we have no way to know and assume when it's included in shipping and handling to auto purchase it which is what 99.9% of people mean to happen in that case.
If you file a support case and include the sales transaction id's where you had local pickup we'll refund those for you. I listed 2 above but didn't check any others. You'll want to edit your saved listings and maybe any listings running on eBay with no bids to remove the insurance option on local pickup.