Cherry-picking is potentially misleading; [url=“http://www.geography.learnontheinternet.co.uk/images/popn/gpw2.gif”]here is a world map showing population densities; certainly there are areas of the UK that are less densely populated than certain areas of the USA, but the less-populated areas of the UK are (by comparison to the USA) still geographically adjacent to the highly-populated areas, so the logistics of outreaching mail to them should be simpler than they are in the USA, where a lot of areas are not only less densely-populated, but are also far outlying from the nearest dense population centre.
Cool. This version of that map works a bit better, Mangetout, being the interactive source of the image. Let’s me click myself off into the wilderness…
Yeah. I just wish that the database the Royal Mail flogs to everyone would have my address listed correctly. i.e. in a way which enables the postman to find my house, and not any of the others with a number ‘3’ within a hundred yard radius. Ho-hum, it’s an excuse to not pay the phone bill on time 
No. It is turned over to the USPS for thier normal delivery. They do not have a stateside delivery operation. NOTE: Is is mail!
The book should end up at your routine mail pickup/deliver point. You may want to notify them to hold the book for your arrival.
RFD is not what it used to be. Some locations are “Way Out” and are no longer serviced as I understant it.
There are in fact nine-digit ZIP codes (“ZIP+4”) that can be used at the sender’s option, instead of the more typical five-digit ones. The extra four digits identify (I believe) an individual delivery route within a zip code district, and can speed your mail’s arrival time by, oh, anywhere up to a day.
Or at least, nine-digit ZIP codes used to make a difference. With modern computer processing, it’s probably just the same now.
Zip/post codes are borderline redundant now anyway. They are only really useful for letters privately mailed by individuals. The real information is in the barcoding on the letter. In Autralia, for example, every dwelling has its own unique code. The owner never needs to know this code, but the OCR equipment at the post office will work it out from the address, and even though our postcodes are only four digits (representing an entire town or suburb each), a letter coming to me will be sorted by the machinery into a tray of mail that represents one postman’s individual beat. For bulk mailing, the customer will often have the entire national database of dwelling IDs on file, and will preprint the barcodes on the envelopes before they even go anywhere near the postal system, in exchange for a discount on postage. Zip/postcodes nowadays merely act as a doublecheck in the case of an error in the address or in the case of handwritten stuff the machines might encounter difficulty with, but this represents a very small fraction of mail. For the most part, an item with the code entirely omitted will sail through the system just as fast and accurately as all the rest. The codes are nowhere near as vital as they once were.