DirectGardening.com shipped incorrect order, would not replace bloomington, Illinois

I purchased for the first time from directgardening.com in July 2009.  I ordered several thing, but among the plants, I ordered 4 sea holly.  The order arrived in August and was enclosed in a plastic bag with the label glued to the front (as shipping and order information)

Instead of the 4 sea holly there were 4 water lillies (for ponds, I don't have a pond and cannot use them).  I immediately called the 800 number on the package and spoke to a nice man who told me to keep the lillies and he'd send out the corrected shipment.

After a few weeks of hearing nothing, I emailed them about the replacement.  I was told that they had no information on that and I needed to resubmit the order using the packing label, which I could not remove from the package and had been destroyed.  I still had my email receipt, I still had the 4 water lillies.

Several emails later, they asked for the same information again, and I included everything.  They then told me it had to come in regular mail and I need the label off the packaging, which once again I had stated I didn't have.  They said that they then needed proof of payment. I downloaded the statement from my bank and copied it and sent it as an attachment. 

They then told me they could not honor that.  I asked them again, to please check their records, they must have some internal mechanism to see that I indeed ordered (I still had the original emails of the order and the confirmation and the shipping) and that I had paid (and I had sent on several occasions the proof from my bank that I had paid for the order). 

They still refuse to ship my plants to me.  They have not ever told me what happened after my original phone call or why I need the shipping label as the person I first spoke with on the day they arrived had told me it was all set, so though the label was destroyed, I no longer needed it anyway. 

The fact that they would allow a screw up involving 4 plants to ruin a company's reputation is beyond me.