I don't think that the collector's edition comes with the soundtrack in a separate case, I think it is like the Game of the Year Edition in that the CD is in the game box with the DVD. You are talking about CDs, right? Though if it was in a separate case it would be cool.
Given that it would require more manufacturing and designing to make the soundtrack and that this is usually done before a game comes out, I think that chances are slim. But doable, if StarClad decides that they want to do it. Yarlen has given a hint about the Kols being sold separately from the rest of the Collector's edition. We will just have to wait and see.