I understand what you are saying, the amazon shipping price is quite high to the US. It is actually variable based on location, so people in the UK get the book for 1p + £2.75 (I believe), and people in Europe pay £3.50 or so. Amazon is in control of the checkout, when the shipping price is displayed, etc.
This order and payment processing go completely through amazon. I sign the books, and someone works in the office to pack and ship them. The wholesale cost of the book is £3.55, so even if you were Amazon buying the books, you'd end up paying more. UK Retail price is £7.99, the book is unavailable in other countries, and I tried to add some value by signing them.
I'd like to have US distrubution too, but there are a couple of big logistical obstacles to me offering a 1 cent book in the near future.
Anyone who is in the US who thinks they have paid too much shipping, I'd be happy to refund $5 of the price, just send a paypal money request to me at firstname.lastname@example.org
and i'll take care of it personally.
In terms of mailing lists etc, there is a link on all mails to "unsubscribe". This should obviously work, but is not a manual process. Lists are managed by the mailing company (usually their name is at the bottom) and it's possible to sign up for multiple lists with the same company if they have different offers that you register for.
My philosophy on the mailing list at PUAT is to give much more free content than anyone else, the ratio is more than 5 piece of good content to every email about a product. I generally get feedback that people like our list a lot. If you have any comments on stuff like this i'd be happy to hear them, but then again running a business requires customers so we have to tell people about products now and again.