Hi Mary, I first found Frank Speher [Census spelling] in 1910, Deer Island, Columbia Co., OR. He was b. Austria, 45, single, immigrated in 1886, naturalized before 1910 and a woodsman logging camp.
In WA state the naturalization papers are filed in the Court House where it occurred. I'd try Columbia County, OR.
In 1920 Frank and family were living in Yankton, Columiba Co., OR. Frank, b. Austria, 54, immigrated 1886, pending naturalization application, woodsman lumber camp; Anna M. b. Finland, 45, immigrated 1885, naturalization status unknown; Eddie O. Hamlin, stepson, b. WA, 24, single, logger lumber camp; John B. Hamlin, stepson, b. WA, single, laborer saw mill; Louisa Plum, stepdau, b. WA. single; Frances Spehar, dau, b. OR, 11/12ths; and Lester Stewart, step grandson, b. OR, 2 3/12ths.
An Anna Spehar married in Linn Co., OR 4 Sept. 1920. Source: OR Marriage Index 1906-1920.
In 1930 Frank and some of his family are living in Dryad, Lewis Co., WA. Frank, b. Austria, immigrated 1891, naturalized before 1930, 42, logger log camp; Anna M., b. Finland, immigrated 1896 and naturalized before 1930 Census, 54 and Frances Spehar, dau, b. OR, 11.
Columbia County Oregon History & Genealogy, www.rootsweb.com/~orcolumb might have more information about them when they lived there. Successful Hunting!