Wow — this question opens up more than you'd think, because there are several novels titled 'Last Call' and release info depends on which one you mean.
If you mean Tim Powers' 'Last Call', that novel originally came out in the early 1990s and has been reprinted in paperback and ebook formats since then; you can usually find new copies through Amazon, Barnes & Noble, Kobo, and Apple Books, and used copies on AbeBooks or eBay. If there’s a newer 'Last Call' by a different author (publishers sometimes reuse the title), the best direct routes are the publisher’s store page or major retailers — they list release dates, ISBNs, and formats. For collector’s editions or signed copies, check the author’s website, publisher newsletters, or specialty shops.
If you’re hunting right now, search the ISBN on Goodreads or WorldCat to see the latest edition and which libraries or stores carry it. I love tracking down editions, so whatever version you chase, there’s usually a pretty satisfying route to owning it.