The Catholic reaction to the HHS Mandate has made it on to the major Media and will be a topic of discussion for a little while at least.  To help you understand why Catholics are strenuously opposed to this move by the Obama Administration, we are gathering insights and thoughts from other sources.

As a short, clear, concise description to why Catholics should be opposed to this mandate, I (the Webmaster) recommend the commentary by Fr. Robert Barron.
Fr. Robert Barron on his "Word On Fire" Commentaries has some excellent insights into why the HHS Mandate really represents an assault on our Catholic Identity, how it is unconstitutional under the the First Amendment, and how it demonstrates a clear betrayal of the principles Obama promised to follow in his famous Notre Dame Speech.
http://wordonfire.org/WOF-TV/Commentaries-New/Fr-Barron-comments-on-the-HHS-Mandate.aspx

Recently Lavinia mentioned 2 articles published by US Catholic Bishops regarding the HHS Contraception Mandate.  She specifically mentioned the writings of Archbishop Timothy Dolan (soon to be Cardinal) of New York and Archbishop Chaput of Philadelphia. Both of these statements can be downloaded in pdf format.
Archbishop Dolan's Wall Street Journal Article
Archbishop Chaput's Special Alert

Below is the Link to the Website of the Catholic Diocese of Lexington on which can be found the comments of Bishop Ronald Gainer of the Diocese of Lexington including his homily of February 6th and his letter to the diocese.
Lexington Diocese Website