well tried to format (again) through file manager. Nothing that I can see. As soon as it's through formatting, the SD just disappears and won't reappear unless I manually restart (actually taking the battery out) because the screen gets locked at the white "NOKIA" screen.
Tried: dd if=/dev/zero of=/dev/mmcblk0 and this is what happened;

/home/user # dd if=/dev/zero of=/dev/mmcblk0
dd: writing '/dev/mmcblk0': Input/output error
15753+0 records in
15752+0 records out

So just tried skipping ahead to sfdisk /dev/mmcblk0 -uM.
errors that it was in use etc. tried to force it through and this is what I got.
sfdisk /dev/mmcblk0 -uM --force
Checkingthat no-one is using this disk right now...
BLKRRPART: Device or resource busy

This disk is currently in use - repartitioning is probasbly a bad idea
Umount all file systems, and swapoff all swap partitions on this disk.
Use the --no-reread flag to suppress this check.

Disk /dev/mmcblk0: 30304 cylinders, 4 heads, 16 sectors/track

sfdisk:ERROR: sector 0 does not have an msdos signature
/dev/mmcblk0: unrecognized partition table type
Old situation:
No partitions found
Input in the following format; absent fields get a default value.
<start> <size> <type [E, S, L, X, hex]> <bootable [-, 8]> <c, h, s,> <c, h, s>
Usually you only need to specify <start> and <size> (and perhaps <type>).


what should I do? **still very confused**
I wouldn't think that this would be such a difficult procedure.