The chairman of the tax-law-writing House Ways and Means Committee has been hit with more than 2,000 letters from angry, befuddled taxpayers complaining about the tax changes he once billed as ``simplification.'' Even Rep. Dan Rostenkowski acknowledges now that the system didn't get much simpler _ he blames last-minute tinkering with the Tax Reform Act of 1986 _ and he says the flood of complaints doesn't surprise him. ``We have been waiting for something like this to happen,'' Rostenkowski, D-Ill., said Thursday. But he said he had expected even more letters to arrive as today's filing deadline approached, perhaps closer to the 10,000 he got after inviting people in a 1985 television address to ``write Rosty'' if they wanted simpler tax laws. ``I must say, it's a dog that didn't bark as far as we're concerned,'' Rostenkowski said. ``There are very few individuals who are writing.'' Committee aides said most of the letters contain copies of an article in Money magazine's April issue lambasting parts of the Tax Reform Act of 1986. ``Fight back,'' the magazine said. ``Send a message to Washington by checking off the boxes by the laws that outrage you, ripping out this article and sending it to the top tax lawmaker: The Hon. Dan Rostenkowski.'' The article criticized nine tax provisions, including a limit on the deductibility of individual retirement accounts, elimination of a deduction for married working couples and a higher threshold for claiming medical deductions. ``There is a lot of frustration out there, and what we're trying to do is address it,'' Landon Y. Jones, Money's managing editor, said of the mail-in campaign. ``People are mad,'' he said. ``They're mad about tax reform. They're mad about how long it took them to fill their forms out. They're mad about losing their IRA deduction.'' Pointing to two huge boxes of mail, aides said Rostenkowski has gotten more than 2,000 letters in a couple weeks _ with no end in sight _ from angry taxpayers. ``In the name of tax reform and simplification, the federal government has once again botched it,'' wrote a couple from Denver, Colo. ``Would you believe there are parts of this country where you can't support a family and live in a decent neighborhood on $50,000 per year?'' said a letter from New Jersey. ``There are, and the situation is worsening.'' From Kankakee, Ill.: ``Being a middle-class American, I feel that once again we are the ones supporting our government, paying for Public Aid persons who could help themselves and carrying the wealthy people right along. When can we expect a change in the attitude of the government?'' The Internal Revenue Service says the changes are not without benefits, bringing lower maximum rates for most taxpayers and an increase in the average refund from $806 last year to $825 this year.