Infrequently, used versions of the official cassettes appear for auction. If you find someone selling MP3 versions of the show, then they are likely pirated copies.
The cassette release contained the following episodes:
Season 1: Episode 1: The Sun Stealers
Season 1: Episode 2: The Starsmith Project
Season 1: Episode 3: The Night Riders of Kalimar
Season 1: Episode 4: The Resurrectionists of Lethe
Season 1: Episode 5: The ISA Conspiracy
Through the official website, all of the episodes were available on recordable compact disc. This includes the last 4 episodes that were recorded but never aired.
As far as I know, the CDs were only released through the official Alien Worlds website. At the time of this writing, the official website no longer exists. The CDs were not pressed silver CDs. They were CDRs with a sticky paper label. Unfortunately, the physical quality of these discs was low and they deteriorated after a few years, and could no longer be played. This is likely due to a combination of low quality CDR material along with the use of sticky paper labels on the CDs causing the bits to disappear over time. Because the CDs deteriorated so quickly, it is unlikely that you will find official CDs on the secondary market.
The official CDs used perforated inserts in the CD case. The
printing was low quality as well. The CDs sleeves appeared to
printed on a standard home type of printer circa 2000 - 2010, and then the
label perforations were torn and then placed into the cases. I had
purchased my first CDs from the website in 2000.
The official CDs for the “Sun Stealers” have a very different ending from the broadcast discs. The usual music is played but no credits are given. At the end of episode 1 part 1 Roger Dressler says the following, “This is Roger Dressler inviting you to stay with us for the conclusion of The Sun Stealers on the world premiere of Alien Worlds.”
At the end of episode 1 part 2, Roger Dressler again has a different voice over in the official release compared to the standard broadcast version. The order of the credits are different and some of the names are different. Part two ends with the following: “Alien Worlds was created, produced and directed by Lee Hansen; Associate producer, Jeff Alan; Music Director Tom Rounds; Original music by the London Symphony Orchestra composed by Jim Kirk and Rich Fox; Story by Lee Hanson and Mike Hodell; Alien Worlds starred Chuck Olsen, Linda Gary, Bruce Philip Miller, Phil Discken, Cory Burton, Bob Taylor, Grayden Gould and Pat Paris. Our engineer was Stu Jacobs; Production Coordinator Erin O’Neal; Assistants to the producer included Johnny Krajeski, Lori Tyler, Sue Cohen, Randy Blotky, and Roger Helms; Technical Consultant Peter Sky; This is Roger Dressler; Thank you for joining us for the world premiere of Alien Worlds.” It also sounds like there is something edited out between “Peter Sky” and “This is Roger”. It was probably the distribution credit.Official CD Case Front Insert
The above image is from the unreleased season 3 disc 1. I believe all of the official CDs looked like this. I had purchased these CDs in 2000 from the official website and years later the cover pictures were still unchanged. Also note that on this one it lists "The Parallax Deception". On the episode itself, the narrator, Roger Dressler, states the episode title is "The Adventure of the Parallax Deception."Written by Ferin Films