His lengthy career in computer high-tech trade press magazines began at IDG and then moved to Ziff-Davis, and included PC Week (later eWeek).
He has been active as a film producer-writer-director since 1997, and continues to work as a journalist in the high-tech and medical industries.
Frentzen co-wrote (with David J. Schow) The Outer Limits Companion (Ace Books, 1986), and in 1998 published Javascript Annotated Archives (Osborne/McGraw-Hill, Berkeley), co-written with Henry Sobotka and Dewayne McNair.
[3] He is the pseudonymous author of three novels, The Bayou Brigade (1981) and Star of Egypt (1981), part of the "Ben Slayton, T-Man" series from Warner Books, writing as "Buck Sanders";[4] and a self-published novel, My Summer With the Family (1992), authored by "Joe Hudson."
In 2014, Frentzen wrote the documentary, Ode To My Mother, and has also produced or directed a series of music videos for folk rock performer Janine Ferguson.