If it's only a handful of files, try:
[tt]fileplace -piv <filename>[tt]
for each one.
According to the man page, this "displays the list of file and indirect blocks in terms of underlying physical volumes, and includes statistics about the efficiency of the placement."
If there are a lot of files, you could use just the -p option and parse the output with a script.
Rod Knowlton
IBM Certified Advanced Technical Expert pSeries and AIX 5L