OK, bit of an update on what I ended up doing.
[The URL shortening discussion is interesting, I myself do not like clicking on shortened links, but acknowledge that if you have to type them in manually, or in Twitter or some other length constrained service, that they do have a purpose -- and I see no harm when the shortened link is to a distinct (not redirected) URL, thus whatever the rules of this forum, kind of no harm-no foul on the amazon or youtube shorteners, where you do know where they are going]
Anyway, what I managed to do is buy a Kobo gift card at Fry's Electronics, and I mailed that out to my relative for the Christmas present. It was not what I would have liked to do, which is to give the books directly, and the Kobo web site is pretty confused (at least in the U.S.) as to eGiftcards, but it did get it right:
http://www.kobo.com/giftcards/wheretobuy
Which lists Fry's Electronics as the only US based retailer of Kobo Gift Cards. Fry's made me sign something saying the gift card was not returnable, also not conducive to my confidence that everything would work properly.
I was sorely tempted to give my relative a Amazon Kindle, to replace her Sony eReader, but I figured to stay within the spirit of her original decision. I sure wish Amazon and the ePub folks would bury the hatchet and make their books readable on anyone's eReader, but I doubt very much I will see that any time soon (outside of iPads and Android tablets). I would definitely buy an eReader that supported both. And if I were to buy an eReader today, it would definitely be Amazon's Kindle, there's an ecosystem around it where things "just work".
One last note, to Kobo, in case there's someone lurking from there. I would have bought my relative two $50 gift cards, if I was absolutely sure that the card would work (and that Kobo would be around in a few years, all this confusion on the web-site and lack of eGift or eGiftcard capabilities is not reassuring). But instead I went with one $50 gift card, and shifted the additional spending somewhere else. So the lack of function or capabilities or availability of gift cards
is costing you revenue.
FUD