Letters? Email? If I don't have some kind of contact within 10 days with either a tracking number, a shipping notification, or at the least a very good explanation, I request contact information from eBay and start making phone calls.

I had one instance where I won an auction for a motherboard, and the seller's only accepted payment method was money order. I sent him an email requesting an address to mail it to an never got a response. 12 days later I started calling his house. I never received a reponse of any kind. I sent him an email saying that I didn't care anymore and that he could go ahead and sell it to someone else. I bought the motherboard from NewEgg. Happy now.

Anyone with any sort of reasonable feedback, either from selling or buying, should understand the process. If they are either unwilling or unable to complete their end, as is obvious here, then I don't see a problem with "going for the throat." Whether this person meant to or not, he/she has stolen money and time from you. The amount of money doesn't matter; the fact that it occured does.