The trouble with word-of-mouth buzz on TV skeins is that it’s hard to come by — and even harder to quantify.

But nets and cablers have found a way to stir some up on their own, with the help of upstart marketing firm House Party Inc.

The Irvington, N.Y.-based company specializes in setting up thousands of pre-premiere viewing parties for shows in the homes of TV enthusiasts around the country. Hosts aren’t paid or reimbursed for their expenditures, but they are provided with custom “party packs” full of themed tchotches, decorations and, of course, a DVD of the program.

House Party facilitates at least 1,000 parties for every project it works on, each with at least 15 guests but often more like 30-40. They’re usually held a week or so before the show’s on-air debut to allow maximum post-party buzz to surface on the Internet.

Indeed, House Party’s top requirement for selecting party hosts is that the person be computer- and blog-savvy. Part of the host’s duties are to write about the event, before and after, and post photos on the microsite set up for their party. Guests are also encouraged to log on and gush.

Last month, House Party organized more than 1,000 Jedi-friendly bashes to help tubthump the Oct. 3 bow of Cartoon Network’s “Star Wars: Clone Wars.” The company also worked extensively with TNT on events for the launch of Steven Bochco‘s legal ensembler “Raising the Bar” as well as the season preems of “The Closer” and “Saving Grace.” NBC has enlisted House Party on events for “Lipstick Jungle,” “The Biggest Loser” and “Friday Night Lights.”

The Disney Channel has also been active in organizing local events around its telepics, partnering with the YMCA to sponsor parties for last year’s “High School Musical 2” debut, and this year it teamed with the Girl Scouts for the latest “Cheetah Girls” movie.

Marketers say in a world of clutter and seemingly endless entertainment options, anything that gets awareness up for premieres is a welcome tool for nets.”Any time you can get a bit more localized, and get that much closer to families in their homes or communities — that’s almost the most valuable marketing you can ask for,” says Richard Loomis, Disney Channel’s senior veep of marketing and creative.

A few random parties organized by diehard fans may not make a difference, but get more than a thousand events going on the same weekend and there’s measurable chatter on the Internet. And compared to the cost of national ad time and outdoor advertising, the marketing value derived from a few thousand party packages is cheap.

“We love it because it’s grass-roots, highly personal marketing that is not just contained to the party. The people go online and start chatting about it. They go on message boards and other (TV-centric) blogs and the whole thread just takes off from there,” says Tricia Melton, senior VP of entertainment marketing for TNT, TBS and TCM.House Party particularly likes to get cast members — or stormtroopers, in the case of “Clone Wars” — to drop in unannounced at selected events. “Raising the Bar” star Mark-Paul Gosselaar made the rounds of parties in Philadelphia, Chicago and New Jersey,to the delight of partygoers.

Other than the occasional thesps, however, there are no reps from House Party or the nets hanging around incognito at the parties. That’d be a major buzz-killer, according to House Party CEO Kitty Kolding.

“Authenticity is important,” she says. “We want people to feel very natural at these events.”

Kolding touts the 3-year-old firm’s rigorous screening process for hosts. Not only do they need to be blog-skilled, but they have to be well-liked in their neighborhoods and social butterflies, too.

“If you haven’t had a party in 10 years, we’re probably not going to pick you,” Kolding says.