NEW HYDE PARK - Even though Long Island's unemployment rate is hovering just below 8 percent, some local companies say they have dozens of unfilled, high-paying positions but cannot find the right applicants. Matthew Sher, who owns a 24-hour plumbing and air conditioning service, says he has at least 20 job openings that pay from $25-75,000 annually. He says the problem is that not enough trained applicants are signing up for blue-collar jobs. Economist Dr. Pearl Kamer says the lesson is that Long Island's schools should offer more trade school options so students have alternatives to traditional college educations.