Protecting Children From Internet Pornographers Act of 2011 - (Sec. 2) Amends the federal criminal code to prohibit knowingly conducting in interstate or foreign commerce a financial transaction that will facilitate access to, or the possession of, child pornography. Makes this prohibition inapplicable to a financial transaction conducted in cooperation with, or with the consent of, any federal, state, or local law enforcement agency.

(Sec. 3) Adds as predicate offenses to the money laundering statute provisions regarding: (1) such financial facilitation of access to child pornography, and (2) obscene visual representation of the abuse of children.

(Sec. 4) Requires a commercial provider of an electronic communication service to retain for at least one year a log of the temporarily assigned network addresses assigned to subscribers or customers that enables the identification of corresponding customer or subscriber information. Prohibits access to such records from being compelled by any person or nongovernmental entity. Directs the Attorney General to study and report within two years on the provider compliance costs. Encourages providers to: (1) give prompt notice to customers of a breach of such records, and (2) store such records securely to protect customer privacy and prevent breaches.

Directs the Attorney General, within two years, to complete a study of providers affected by this section, including: (1) the privacy standards and considerations implemented, and (2) the frequency of any reported breaches.

(Sec. 5) Bars any cause of action against a provider for retaining such records as required.

(Sec. 6) Makes a good faith reliance on the record retention requirement a complete defense to a civil action.

(Sec. 7) Allows the issuance of an administrative subpoena for the investigation of unregistered sex offenders by the United States Marshals Service.

(Sec. 8) Requires a U.S. district court to issue a protective order prohibiting harassment or intimidation of a minor victim or witness if the court finds evidence that the conduct at issue is reasonably likely to adversely affect the willingness of the minor witness or victim to testify or otherwise participate in a federal criminal case or investigation. Authorizes the court to: (1) issue an ex parte emergency protective order in advance of a hearing if exigent circumstances are present, in which case the court shall hold a hearing not later than 14 days after the date such order was applied for or issued; and (2) order that such a protective order expires on the later of three years after the date of issuance or the date of the minor victim's or witness's 18th birthday. Provides for up to five years' imprisonment, a fine, or both for violating or attempting to violate such a protective order.

Directs the courts to presume, subject to rebuttal by the person, that the distribution or publication using the Internet of a photograph of, or restricted personal information regarding, a specific person serves no legitimate purpose, unless that use is authorized by that person, is for news reporting purposes, is designed to locate that person (who has been reported to law enforcement as a missing person), or is part of a government authorized effort to locate a fugitive or person of interest in a criminal, antiterrorism, or national security investigation.

(Sec. 9) Directs the United States Sentencing Commission to review and, if appropriate, amend the federal sentencing guidelines and policy statements to ensure that such guidelines provide an additional penalty for obstruction of justice associated with sex trafficking of children and other child abuse crimes.

(Sec. 10) Imposes a fine and/or prison term of up to 20 years for a child pornography offense involving a prepubescent minor or a child under the age of 12.
Output: To amend title 18, United States Code, with respect to child pornography and child exploitation offenses.