LinuxQuestions.org - manually write partition table for deleted partition

i was installing ubuntu jaunty few days on my new laptop hp-dv6(320gb hdd)
and had backed up my data in my 160 gb external portable hdd
i accidently deleted my partition of external hdd and went ahead and started installing ubuntu
then i suddenly realised my mistake and immediately pluged out the ext hdd knowing that data is still there and only partition entry has been deleted
i thought that recovery would be easy
googled and found tools like testdisk, active partition recovery.
tried them but unfortunately none worked(dont know why)

after finishing scanning the hdd for lost partitions and correctly detecting that one big 160gb partition has been deleted active partition recovery gave error msg that disc MBR damaged and it cannot continue so i selected option to rewrite fresh mbr on the hdd
this was the only change i made to my hdd

then i tried testdisk
to my horror it didnt show ny partition

so i kept ext hdd away for 2-3 days and played with my lappy on ubuntu(as its 320 gb hdd had no data so i could safely do nything)
and now i have a perfectly working ubuntu jaunty on my laptop

since i didnt write to my ext hdd all the data should be there
i as hoping that if i could manually rewrite the partition table so that windows would feel asif no change has been made to partition

how can i do this plz tell
ny help is welcome
but plz dont suggest ny softwares for searching for lost partitions
guide me how to write the partition table fore the lost ntfs 160 gb partiton which filled the entire 160gb ext portable hdd