LAS VEGAS - The homebuilding industry's biggest trade show meets this week, but most of its biggest executives will not be there.

The International Builders' Show, happening this week in Las Vegas, is the marquee event of the homebuilding industry, equivalent to the Consumer Electronic Show for technology or Fashion Week for retailers.

It will attract about 55,000 builders, contractors and other industry professionals to a maze of booths and exhibits featuring more than 1,000 companies selling everything from skylights to stoves.

But the star power that lit the scene in the past has dimmed. Leaders of many of the industry's household names, such as Pulte Homes Inc (PHM.N), Toll Brothers Inc (TOL.N) and Lennar Corp (LEN.N), will skip the show, although some will send lower-ranking executives.

Pulte CEO Richard Dugas will not attend. Nor will Lennar Corp (LEN.N) CEO Stuart Miller, Toll Brothers CEO Bob Toll or Hovnanian Enterprises Inc (HOV.N) CEO Ara Hovnanian.

Such executives were once regular attendees, drawing crowds to panel discussions and generating excitement on the show floor.

Their absence arises as the executives make plans instead to meet under the auspices of their own new trade association, the Leading Builders of America, in February, said Executive Director Ken Gear, a former vice president for government relations for Pulte, the biggest U.S. homebuilder.

The big builders decided they wanted a more direct connection to lawmakers after their experience lobbying the government for aid to combat the industry's protracted down turn, Gear said.

Business remains tough for builders of all sizes. Even as much of the industry milled about here, inspecting the latest green appliances and networking, the National Association of Home Builders, which runs the show, announced its index of builder sentiment fell one point in January to 15. A reading below 50 means more builders view sales conditions as poor than good.

Against this bleak backdrop, the new group's first meeting, tentatively planned to coincide with an investor conference the builders' executives will attend in Scottsdale, Arizona in February, will focus on housekeeping and agenda-setting, said Gear.

Until this year, the International Builders' Show hosted its own forum for the biggest companies at its High Production Home Builders Council. That council no longer functions, said Paul Lopez, an NAHB spokesman.

The new group grew from big builders' efforts on behalf of the homebuyer tax credit and the extension of a tax provision that lets companies get refunds by using losses to offset prior income.

Conflict arose when the smaller builders, afraid their bad situation could worsen, objected to the tax provision extension. They feared their bigger rivals would exploit it by dumping land on the market. Too much of that could drive land values and home prices down further, jeopardizing the survival of less diversified builders.

The big builders and a broad coalition of other business interests won the tax provision extension in the end, but it is impossible to say which builder camp will prevail in general when their interests clash, said Michael Boland, a longtime Capitol Hill hand whose company, Dome Advisors, does political risk research for institutional investors.

Each group has its strengths, said Boland.

Most of the financial clout will be in the Leading Builders of America. The grassroots power will be in the NAHB, he said.

The Leading Builders of America has no plan to start its own political action committee, Gear said. Such a group would compete with the NAHB's BUILD-PAC. Gear declined to disclose the new group's dues' structure.

The national companies remain NAHB members, but instead are sending other executives, division presidents and purchasing agents to this year's show. Deborah Meyer, Pulte's new chief marketing officer, will be there to get broad exposure to the industry, spokesman Caryn Klebba said. Meritage CEO Steven Hilton will speak on a panel at the show, spokesman Brent Anderson said.

Even big builders still find the show useful, said Toll Brothers President Zvi Barzilay.

Barzilay and his colleagues plan each morning how to attack the show and meet each evening to review what they have learned, he said.

There is a lot to absorb here, he said.

Still, there used to be more. The downturn has shrunk the show. Attendance is a little more than half what it was at its peak in 2007, the NAHB's Lopez said.

There are a lot of builders here, big and small, Barzilay said. But a lot less than have been here in the past. It's obviously a reflection of the times.

(Reporting by Helen Chernikoff; editing by Robert MacMillan and Andre Grenon)