Wednesday’s release of the movie trailer for The Hobbit: An Unexpected Journey, the first part of Peter Jackson’s movie trilogy based on the J.R.R. Tolkien classic, is boosting the excitement surrounding this year’s Hobbit Day, which will be celebrated worldwide this coming Saturday, Bilbo Baggins’s birthday. It’s also the birthday of his nephew, Frodo, from the Lord of the Rings trilogy. Another milestone occurs this week: Friday marks the 75th anniversary of the publication of The Hobbit. And some booksellers have already gotten in the party mood, with an assist from more than 1,000 event kits, which Hobbit publisher Houghton Mifflin mailed out to bookstores, teachers, librarians, and homeschoolers, along with movie posters and “for President” buttons.

Things got rolling on Tuesday at newly opened Acorn Books in Dover, Del., which hosted its first event, a launch party for Corey Olsen’s Exploring J.R.R. Tolkien’s The Hobbit (Houghton Mifflin), with cupcakes iced with the title of the book. Thirty-five people braved “nasty” weather and the book sold out, according to co-owner Ginny Jewell. Olsen will host a day-long “virtual festival,” which will be live-streamed on [the Hobbit Day Web site] on Saturday, and make appearances at a number of book festivals later this fall, including ones in Miami and Boston.

Some bookstores with cafés, like Phoenix Books in Essex, Vt., are going all out with Hobbit-friendly menus: First and Second Breakfast, Hobbit Tea, Long Trail Ale, and Bilbo’s Teatime Scones. “We’re having a good old time,” says co-owner Michael DeSanto, who has been rehearsing with two staffers for a reading from The Hobbit at the store party on Saturday. He had been planning to buy a screen and projector later in the year for Skype events, but moved up his purchase so that partygoers can view a special longer edition of the movie trailer that Warner Bros. is making available to booksellers. With the extra push, DeSanto says, he’s seeing “heightened” sales.

Other booksellers report a similar bump. “We’ve actually been selling an increased rate of The Hobbit and the Lord of the Rings since last December and the release of the trailer. This is really an acceleration of the trend,” says Jeff Wood, owner of Whistlestop Bookshop in Carlisle, Pa. He’s planning a big party for Hobbit Day, although, he notes, “it’s not going to be as wild as a Harry Potter party..” Still, he’s heard from customers in Virginia and New Jersey who are planning to make the trip.

At Annie Bloom’s Books in Portland, Ore., bookseller Kate Stone has been building a giant piñata for the past several days – decorated with the cover of The Hobbit –for a party designed to attract “children of all ages.” The store is planning craft activities and a trivia quiz. But it’s still too soon to see an impact on sales, according to Stone. Although she’s not sure how many kids will show up in costume, other stores are making efforts to ensure that plenty of Bilbos and Gandolfs are in attendance. At Burlingham Books in Perry, N.Y., each person who comes to Bilbo's birthday party on Saturday will receive a special gift.

Some stores are zeroing in on older readers. BookPeople in Austin, Tex., is holding a costumed Tolkien Trivia Night on Friday to raise money for Save Our Springs, a local alliance that works to protect an Austin aquifer and surrounding streams. For $50, teams of four can register to answer questions written by the store’s booksellers. Complimentary food includes Hobbit pizza.

While it may be too early for bookstores to feel the full impact of Tolkien-mania, Houghton Mifflin is ready with a 600,000-copy first printing of the movie-tie-in edition of The Hobbit along with a 300,000 copy printing of a 75th-anniversary edition. It is also releasing 150,000 copies of new black-jacketed editions of each of the books in the Lord of the Rings trilogy and 100,000 copies of a boxed set of the new black books, with The Hobbit and Lord of the Rings packaged together. “Middle-earth is one of those places that readers identify with and love to inhabit through Tolkien’s work,” says v-p and director of trade paperbacks Ken Carpenter, who oversees the Tolkien publishing program. “There are many titans of science fiction/fantasy, and Tolkien is the granddaddy of them all.”