Mm... yeah, with no idea of the prof or the books not assigned, it gets trickier.
The bright side is there's a strongly non-zero chance -- especially with the conditions you've noted -- that the teachers will be understanding and/or supportive of students that don't immediately have their books at the beginning of the semester (and if not, well, kindly point out to them it's their administrative fuckup that's caused this, not yours. In more polite terms, of course, but still.) because the books in question are still on their way. Think the latest I've gotten a book was like 2-3 weeks into the course, a couple of times so far, due to stuff like what you're talking about. Because goddamn hell no am I paying $200+ more than I have to for a textbook, even if it does mean having some difficulty following the class for the first month or missing some assignments or whatever.
Other good idea is to contact your adviser with pertinent information regarding the situation -- they may actually know (or be able to find out) more than is publicly accessible and/or be able to sooth things over with whatever teacher you do end up with, if you do end up having to wait a couple weeks to chop off a couple hundred bucks from a book. Beyond sympathy and understanding, the blighters do want your money (regardless as to if it's you, specifically, or a third party, doing the actual paying), and they're pretty strongly incentivized to bend a little, where possible, to keep you on campus, in classes, and paying tuition and fees. Or, if possible, contact your fellow students. There's a strong possibility that one or more would be willing to share book access for a bit while your own copy is in transit -- maybe in exchange for studying help or a lil'cash or whatev', but who knows.