External Drive used with PS3

Hello,
Admitted computer non-user and I am trying to use external drive (used with my MAC laptop) to view movies on PS3. PS3 not recognizing hard drive. On line advice was to format to FAT32. Opened external drive using my MAC and followed directions step by step....Partitioning etc. It appears that ALL my movies etc. are gone! Can anyone HELP?!? Freaking out thinking i have lost everything. PLEASE HELP?