I have good news and bad news. And also some news that might not be entirely accurate.
The good news: You can now pre-order the paperback and hardcover editions of Joie de Vivre! There were a few hiccups early on that meant only the ebook was available, but it's now looking like these have been solved (or at least, will be solved by the end of the month if not).
The bad news: At this stage, it looks like I can't offer a pre-order discount on the print versions. I'm sorry. I have a lot less control over the pricing of these editions and we've already priced them to the point that I barely get a royalty from them as it is. (If I lived in the US or UK, it would be a different story but because I'm in the arse end of nowhere things are much more complicated).
The "I don't know if this is entirely accurate" news: The print editions, as well as the ebook are definitely available at Barnes and Noble. It looks like they're available on Amazon too--but I am still having some issues and glitches there. So if you're in the US or Canada, you shouldn't have any problems.
For UK readers--it's supposed to be available from Waterstones, but so far I can't see it anywhere on the website. I have no idea when it will be available; it's possible they're not letting me do pre-orders.
For the Antipodes--it looks like it's available on Fishpond, and it's supposed to be available on Mighty Ape but I still can't see it and it might be another situation of them not allowing pre-orders or something.
It's highly likely that it's available elsewhere too, but the aforementioned are the main ones that I'm aware of.