For 15 years Tamarkin was editor of Goldmine, a magazine for record and CD collectors. Prior to that, he served as the first editor of CMJ (College Media Journal) and as editor of Relix. He was also the first editor of Grateful Dead Comix, and has written for many other publications, including Billboard, Pulse, Boston Phoenix, Playbill, Creem, Mojo, East Bay Express, The Aquarian Weekly, Newsday, Sing Out, Tracks, Harp, The New York Daily News and ICE. He has contributed to the Guinness Encyclopedia of Popular Music and Allmusic.

Tamarkin has written the liner notes for more than 75 CDs, for such artists as The Beach Boys, Tom Jones, Jefferson Airplane, Dick Clark, The J. Geils Band, Chubby Checker, Merle Haggard, Dean Martin and many others, including ABKCO Records' Cameo-Parkway label reissue series. He has also served on the Nominating Committee of the Rock and Roll Hall of Fame and as a consultant to the Grammys.

In the course of his work Tamarkin has interviewed hundreds of musicians and celebrities, including Roy Orbison, Brian Wilson, Jerry Garcia, Yoko Ono, B. B. King, Carlos Santana, Dave Brubeck, Ricky Nelson, the Ramones, Herbie Hancock, Ray Davies, Elvis Costello, Dexter Gordon, Peter Tosh, Frank Zappa, Ringo Starr, Solomon Burke, Dionne Warwick, the Monkees, Bobby McFerrin, Pat Metheny, Little Richard, Arlo Guthrie, and Nancy Sinatra. As a consultant to the Music Club CD label, he assisted in releasing over 180 reissues and compilations, in styles including rock, jazz, country, world music and pop.

After writing short books on Billy Joel and Bruce Springsteen, his first full-length book, Got a Revolution! The Turbulent Flight of Jefferson Airplane (Atria Books), was published in June 2003. The first biography of the San Francisco band, it was written with the cooperation of all of the band members and placed the Airplane into the context of their times, the volatile 1960s. Got a Revolution was named one of the best books of 2003 by the San Francisco Chronicle and the Boston Phoenix, and received very positive reviews from, among others, Publishers Weekly, Kirkus, Austin Chronicle, New York Daily News, and The Onion. It was published in paperback in July 2005.

From 2002-2006, Tamarkin was editor-in-chief of Global Rhythm, the leading magazine for world music and global culture, in which he also wrote about music, film, cuisine, politics and other topics. In 2007 Tamarkin was named Associate Editor of JazzTimes magazine. He returned to full-time freelance writing in 2009.

He lives in Hoboken, New Jersey, with his wife, the novelist and book reviewer Caroline Leavitt, and their son Max.