As long as you keep an eye on targeting, and don't get your folders mixed up, you should be fine.

But in the real world, we all make mistakes, right? So you may feel safer by simply adding a different character to each track name for each song. For instance, the "km54(L)" track could be labeled "A-km54(L)" on the first song and "B-km54(L)" on the second song. If you were working on the first song and saw any file labeled with a "B" at the beginning, you would immediately know something was wrong before an unrecoverable deletion. This method still requires careful attention, as mislabeling a track could lead to serious confusion or some distastrous mistakes.

This is the safest way:
1. Open your session
2. Select all unused files
3. "REMOVE" them from audio list. MAKE shure you dont hit "DELETE"
4. Go to File>"save session copy in"
5. Select "include all files" (or something like it)
6. Copy the files to any other drive you have
7. Close the session WITHOUT saving it, so it will be just as it was when you open it.
8. open the new session, should be labeled like "copy of ....."

Repat this for every session where you have "share" files.

.02

Brent,
If all your songs are individual sessions, that is they each reside in their own distinct folders on the hard drive, and are NOT one long session, then deleting files from a particular song should not affect files with similar names in other folders. I say "should" because I don't fully trust the voodoo. The smartest thing would be to back up all your stuff and then go through each song removing the files you don't want, and then check by opening the session to see if all the ones you need are still there. If something goes wrong you've always got the backup. A bit of a PITA and requires the backup space, but if it's important stuff, go slowly and methodically.
Peace,
Yorik

Thank you all for the help! I think I'm getting a handle on this beast...my problem occured because I had imported some tracks from another session/folder thinking it would be stored as a permanent move...then, when I removed the source file from my hard-drive, the tracks disappeared from the more current session. Luckily, I had it all backed-up on some CDRs and was able to import the tracks again. Fun stuff! Learning....thanks again. Much appreciated!

Glad you had the back-up. To avoid the same problem in the future, COPY the required track to the audio folder of the new session, and then import it from within that session and save. But you may have figured that out by now. However, once grasped, file management does get easier.
Peace,
Yorik