Found a lot of stuff
on www.delcampe.net

including e.g. stamps from Congo, magazines , vinyl, cd's

Just search for Frank Zappa

Another tip on Zappa is the on the internet roaming torrent for the bootleg Cucamonga years .

Expanding on Del-Fi/Rhino's 1983 mini-album Rare Meat: Early Productions of Frank Zappa, Japanese label MSI licenses tracks from both Del-Fi and Original Sound Records for its 13-track, half-hour-long compilation
Cucamonga Years 1962-1964: The Early Works of Frank Zappa

. These are recordings that date from Zappa's early years as a songwriter, session musician, and producer at PAL Recording Studio, owned by Paul Buff and Dave Aerni, located at 8040 Archibald Boulevard in Cucamonga, CA, which Zappa subsequently took over and renamed Studio Z. Typical of the pop music of the time, the songs include doo wop, surf music, and even a couple of horror-movie-spoofing novelties in the vein of "The Monster Mash." They were released originally as singles on Donna Records ("How's Your Bird?"/"The World's Greatest Sinner," by Baby Ray & the Ferns, featuring future Mothers of Invention singer
Ray Collins , Donna 1378; "Dear Jeepers"/"Letter from Jeepers," by Bob Guy , Donna 1380; "Every Time I See You"/"Cradle Rock," by the Heartbreakers , Donna 1381) and Original Sound ("Memories of El Monte," by the Penguins , Original Sound 27; "Grunion Run"/"Tijuana Surf," by the Hollywood Persuaders , Original Sound 39; "Mr. Clean"/"Jessie Lee," by Mr. Clean , Original Sound 40; "Heavies"/"The Cruncher," by the Rotations , Original Sound 41) in 1963 and 1964. Zappa wrote or co-wrote most of them and sometimes plays guitar. There are, of course, clues to Zappa's later efforts, especially Cruising with Ruben & the Jets, and "Heavies" is the track that begins the second side of the Mothers of Invention's We're Only in It for the Money before a needle is rudely raked across the record. But this still brief album is intended primarily for Zappa completists.

1 - Penguins - Memories of El Monte
2 - Baby Ray & the Ferns - How's Your Bird
3 - Baby Ray & the Ferns - World's Greatest Sinner
4 - Bob Guy - Dear Jeepers
5 - Bob Guy - Letter from Jeepers
6 - Hollywood Persuaders - Grunion Run
7 - Hollywood Persuaders - Tijuana Surf
8 - Mr. Clean - Mr. Clean
9 - Mr. Clean - Jessie Lee
10 - Rotations - Heavies
11 - Rotations - Cruncher
12 - Heartbreakers - Every Time I See You
13 - Heartbreakers - Cradle Rock

Just back from Hols were I brought a nice Vinyl original pressing of Boulez conducts Zappa: The Perfect Stranger for $50.

I asked this question on Zappateers which no one has replied too. Don;t think they want to eat that question

Thoughts on the next release
https://www.zappateers.com/forums/topics/6185?page=3
"What about when will be the final Official Zappa release - 5yrs , 10 yrs and what should it be??"

I know there is a lot of stuff in the vault but there will come a day when the money dries up, what should be on the final official release?

I can think of a lot of things I don't need to be on it. Zappa was smart in publishing the best of the best, that's for sure.

I'd lvoe to hear more of the Waka Jawaka / Grand Wazoo era.

Agreed, that would be a fitting ending for the official Zappa titles

The sheer volume of stuff that has been released posthumously is a testament to the breadth and depth of the work he produced, but yes, it's finite, so inevitably it'll run out. The number of FZ cover bands, though, is on the rise, and is a good indicator of the continuing interest in his music, so I believe Universal will not have trouble continuing to finance vault releases until those of a tangible release value run out.