The following article says that she is "expected" to form a campaign committee, but a quick check of the FEC's website confirms that her organizational paperwork has been filed as of 9/10/2007, just not uploaded to the site.
In other words, she may not have "announced" as yet, but it's official.
From the Business Journal of Phoenix -
Former state lawmaker and conservative newspaper columnist Laura Knaperek is expected to announce that she will challenge U.S. Rep. Harry Mitchell, D-Ariz., in next year's election.
Knaperek has been discussing a possible run with leading Republicans and business advocates and is expected to form a campaign committee, sources say.
Knaperek joins former congressional staffer and business lobbyist Jim Ogsbury and state Rep. Mark Anderson, R-Mesa, as possible candidates.
Brief background on Laura Knaperek:
She has been a regular candidate in what is currently Arizona's Legislative District 17 (formerly District 27). She won seats in the State House of Representatives from 1994 - 2000, lost to Harry Mitchell in the 2002 race for State Senate from the district, returned to the AZ House in 2004, and lost last year during a Democratic sweep of the races in the district.
A sweep that was led by Harry Mitchell's victory in the CD5 contest.
In addition to the columns that she has written for the East Valley Tribune, since her loss in last year's election, she has been working as the Executive Director of an organization called United Families International. The organization, among other things, opposes UN efforts to outlaw forced marriage and gender-selective infanticide.
Note: Her association with UFI was not noted in the Business Journal article.
In a Republican primary, she will stake out the 'pro-life, hardcore social conservative' territory.
Evaluation: She is a seasoned campaigner with name recognition among the Republican voters in the LD17 part of the congressional district (approx. 35% of the total district). However, she has lost two general elections in the district in the last 6 years, one to Harry Mitchell directly and one indirectly.
More importantly, she has low name recognition outside of her base district in Tempe, and some of the rumored candidates who have yet to announce are from the district (LD8) that makes up the largest part of CD5.
That deficit can be changed with a lot of schmoozing, but she is far more socially conservative than the average "Chamber of Commerce" Republican that is the norm in LD8.
In addition, she burned some bridges within her party during the contest for AZ Rep State Party Chair early this year.
She will have a tough time getting out of the primary.
A PDF of her statement of organization will be available at the link once the FEC has it available.
Her 2003/4 legislator financial disclosure form can be found here; 2005 form here; 2001 form here. Note - she didn't have to file a form for the years that she wasn't in the legislature.