If you are upgrading your kernel then make sure you have scsi generic support and usb mass storage compiled.
When you plug in the disk/device run "dmesg" and this should show the connection and a device and associated partition such as "sda1". You can then mount the device like:
mount /dev/sda1 /mnt
You may prefer to mount to /mnt/camera (just mkdir that directory) and add an fstab entry to make it easier to mount:
/dev/sda1 /mnt/camera auto noauto,user,owner 0 0