glabel(8) should work for FAT32, from the manpage:
Code:
Currently supported file systems are:
o UFS1 (directory /dev/ufs/).
o UFS2 (directory /dev/ufs/).
o MSDOSFS (FAT12, FAT16, FAT32) (directory /dev/msdosfs/).
o CD ISO9660 (directory /dev/iso9660/).
o EXT2FS (directory /dev/ext2fs/).
o REISERFS (directory /dev/reiserfs/).
o NTFS (directory /dev/ntfs/).
Which also answers the question where you can find the labels in /dev/.