This is a 3 CD set.
CD1 and CD2 are the Complete Score, including all the pieces of music that weren't in the 1982 version.  The entire Tower of Set part of the movie is here musically now, as is everything between the Search and the Orgy and all the other scenes like the Wolf Witch, and King Osric.

CD1 Starts off with Track 01 (Mako's) Prologue before going into Anvil of Crom. It ends with Track 19 The Leaving/The Search which is a 6:00 version of the original 3:12 Track 8 The Search.

CD2 Picks up with Track 2.01 Mountain of Power Procession and continues through to Track 2.13 Conan King (End Title).
After that are 8 extras, 5 of which are First Versions of the most iconic tracks of the album. (Anvil of Crom, Battle of the Mounds, etc)

CD 2 ends with 3 very cool tracks.
2.19 is Orphans of Doom with Orchestra but a Solo voice, which makes it more haunting.
2.20 is Orphans of Doom with Harp and Chorus.  Both of these are pretty cool variations.
2.21 is a full 6 minute version of The Snake, which is really based on one of the "Las Cantigas de Santa Maria". (You learn something new every day).

EDIT: 2.06 The Defilers is awesome, it's the music in between the original The Orgy and Funeral Pyre.  If you remember the movie, that music is basically the combat music with Anvil of Crom in the middle.  A go-to combat music track if ever there was one.

One of the greatest movie Soundtracks of all time is now 100% completely assembled and remastered.  
If you liked the Original Soundtrack you'll love this.
If you loved the Original Soundtrack, then this one goes to 11!
If you didn't like the Original Soundtrack...

Spoiler

THEN TO HELL WITH YOU!

That sounds awesome. Basil Poledouris brings a John Williams and Ennio Morricone hand to movies (where half the point is the music). I just watched Starship Troopers again the other night and was struck by how much the music carried the film in the battle scenes. Conan was the soundtrack that got me into soundtracks and eventually led me into classical and a whole host of musical styles I never otherwise would have found. I did't even realize you could buy soundtracks until after I watched Conan and decided I needed to have that music in my stereo.

Don't buy the MP3's, get the CDs and rip to .FLAC files, better sound quality.

Is this a new CD set?

I have this one hotkeyed, I mean bookmarked...
https://www.youtube.com/watch?v=1_xgecR0ifo

I went ahead and ordered the MP3 (I expect you are right about the sound quality Krueger, but the difference in price was too big and I'm cheap---I assume it does that annoying thing where transitions between tracks isn't smooth). Went ahead and picked up Robocop on Blueray as well now that you have me thinking of Poledouris soundtracks.

I've had the soundtrack, but I'm guessing not this super special extended soundtrack, for almost twenty years now.  Only one disc for me, but then I'm find with just the big opening... though the rest is no slouch.