Ok. I have this soundtrack, but I don't really know if it's rip or official.
So, can someone help me to know if there was ever a soundtrack for this released?
it seems this is one of the rarest things to search for. I have not come up with any information about it. Just the Michiaki Watanabe Bgm Collection, where there is some tracks from Kotesu jeeg, but I have more tracks then that. :/
I have 36 tracks, and i don't know even the names or where are they from.
Help? :/???

While this is an old post, I think I should answer it in case anyone else is also looking for info about this topic. As far as I know and there is no official individual release in Japan of the Kotetsu Jeeg (1975) original soundtrack in either LP or CD. It is available, though, in Michiaki Watanabe BGM Collection (1995) in its second CD (COCC-12824). I think that particular collection was shared in the threads Michiaki Watanabe (Soundtrack Music Collection) (Thread 105795) and Bal's Godzilla 'n' other heavyweight beasties share thread ('n' Toho stuff too) (http://forums.ffshrine.org/f92/bals-godzilla-n-other-heavyweight-beasties-share-127297/5.html#post2290423).

The 36 tracks rip roaming around the net seem to be of Italian origin. I do not know if the OST was released officially in that country since the anime was quite popular there and there were many official releases related to the series and several others of Go Nagai. I also have those thirty six tracks mentioned in the post above, and, after doing a short research on them, I believe they come from COCC-12824, but with the individual melodies divided in 36 tracks instead of the suite format that they had in COCC-12824.

From COCC-12824, tracks 1 to 8 are from Kotetsu Jeeg and amount a play time of 29:22 mins. approximately. Of the rip with 36 tracks, playing from track 1 to 26 plus track 36, the ending theme, amounts around 29:22 mins. Why up to track 26? Because track 7 of COCC-12824 ends with the same melody, although it's within a longer suite. COCC-12824, however, has other three bonus track melodies that don't appear to be attached to either Kotetsu Jeeg or Magne Robo Gakeen (the other series in that CD). Those three have around 21:58 mins. in play time. The second track of these starts with the melody that corresponds to track 27 of the other group. Therefore, I assume that the rest of the melodies from the 36 tracks that aren't in the first 8 tracks of COCC-12824 are in these three bonus tracks.

Hopefully, I've been sufficiently clear so that future users know that a Kotetsu Jeeg OST exists, but not as an individual album, at least not in Japan.

2010..... 2010!!!!!!!!!
what a great reply 4 years later XD

I had the same suspicion about the Italian guy bundling together all music he could find. As of that day I quit on trying to figure it out. I still have that rip. funny. Yesterday I passed by eyes on the folder with it and thought to myself "I am never going to have this with current naming on the tracks."

For completion's sake, I've added two topics that have the mentioned albums:

Kotetsu Jeeg Original Soundtrack [BOOTLEG][MP3] (Thread 182711)
Michiaki Watanabe BGM Collection [MP3] (Thread 182717)

Fantastic Jeeg Robot! Thank you!

One final album from my part related to Kotetsu Jeeg. It only has one suite and I don't think there is anything new, but it might be of interest to those fans of the BGM of the series.

Michiaki Watanabe BGM Collection: "Chumei" Brand [MP3] (Thread 182793)