SEATTLE (AP) - Hurricane Katrina destroyed thousands of homes, but it was the damage to timber and sawmills in the storm-ravaged region that immediately drove up the price of some construction materials nationwide. Now, as the plants reopen and the focus switches to reconstruction, experts say prices should begin to stabilize. In the long term, some say the rebuilding effort will have a minimal effect on construction costs elsewhere in the country - and could possibly even lead to changes that make home building somewhat more affordable. "In terms of somebody buying a house in California, there's going to be...