I can see room for several questions and answers:
A: Software. Sure, this is a moving target, but softwarerecs doesn't work. This answer should distinguish between programs that attempt to recover data, and ones that try to rebuild the partition table.
B: Hints. This is a set of answers about signature values that can be searched for with a disk editor to try to determine the original layout of the disk. E.g. is the first sector of an HFSJ+ partition unique?
C: Resources. Links to other web pages that may help.