In a plea to the public to help "free the man we know is innocent," Scott Peterson's (search) attorney is seeking donations to continue the investigation into the murders of Peterson's wife and the fetus she carried.

The 32-year-old former fertilizer salesman was convicted Nov. 12 of first-degree murder in the death of his wife, Laci, and second-degree murder in the death of her eight-month-old fetus. Last week, the jury recommended a death sentence (search).

Formal sentencing is set for Feb. 25.

Los Angeles defense lawyer Mark Geragos (search) has set up a Web site seeking financial help in the continuing search for what the defense regards as the real killer.

"We believe Scott Peterson has been unjustly convicted. This site will continue to monitor the happenings in this case until justice is finally served," the site reads. "With your support, you can help us continue to investigate the murders of Laci and Conner Peterson so that we can free the man we know is innocent."

The site notes that donations will be used only for investigators, not for attorneys' fees.

"For Scott to get the justice he deserves, the investigation must continue. Unfortunately this does not come without a price," the site reads.

Geragos did not return repeated telephone calls.

Meanwhile, Peterson's former mistress, Amber Frey, will appear on "Dateline NBC" Jan. 4 to discuss her book due to go on sale the same day.

Excerpts of Frey's interview with NBC News' Matt Lauer were released Monday to The Associated Press.

Asked what she thought about Peterson's early television interviews, before his arrest, as he pleaded for Laci Peterson's safe return, Frey said, "I just saw him, you know, as this compulsive ..., pathological liar."