GParted is a partition manager you can use to resize, copy or move partition without losing your data.

The latest GParted 0.8, released a couple of days ago, adds an option to rescue data from lost partitions:

KDE Partition Manager allows you to manage your disks, partitions and file systems: Create, resize, delete, copy, backup and restore partitions with a large number of supported file systems (ext2/3, reiserfs, NTFS, FAT32 and more).