I guess it is no use crying over spilt milk or asking what sort of "glitch" in your system required an Erase and Install (I'm curious on that one) What does confuse me is that your backup does not contain the pictures.
Questions:
What, exactly, did you backup from the internal drive to the external? I have a feeling that you backed up the iPhoto Application and NOT the /~/Documents/Pictures/iPhoto Library.
Did you backup your Documents folder? If you did, you are in with a chance of recovery. Check on the external drive for that folder. Check inside for the Pictures folder and inside that for iPhoto anything. If it exists, drag it from the external to the internal and put it in our Documents/Pictures folder. Cross your fingers, restart iPhoto and hold your breath.
If they are not there, I think the chances of recovery as rather slim, even with the big bucks. When you installed Tiger, you Initialized (formatted) the HD. This destroys, for all practical purposes, the data on the HD. This is why is warned you that this was going to happen and even got you to agree to it. Tiger was then laid down on the disk along with all the other bits and pieces including iPhoto, and here is the kicker, OVER the top of where 10.2.8 (and your pictures) was originally installed. Had you stopped after the Erase and before the install, your chances of recovery were good. Now that the drive has been written over, your chances of recovery are less than stellar.
Storing data on a CD is a good idea, ready made for occasions such as this, but erasing the CD, heap bad idea. I have never got into the CD-R/W thing. For the price of a CD-R, < 10c, just burn your copies and store them. Don't use an R/W as permanent storage, chances are that you will need a disk one day and ..........you know the rest.
Let us know about what you actually backed up and whether you found anything
Good Luck
P
I have been really stupid this time!
I upgraded my Mac from 10.2.8 to Tiger, with an Erase and Install (necessary because I had a glitch in my system). I had everying backed up on an external hard disk - so I thought. But when I came to access my iPhoto albums every picture had vanished. Seems to me that the albums must have been merely aliases, and the real stuff was actually on my hard disk. It's really heartbreaking - they were irreplacable photos taken on my digital camera over several years.
How can I go about trying to get them back? They are presumably still on my HD, unless the Erase and Install has destroyed them. They might also be on a CD-RW where I formerly stored all this stuff, but has since been quick erased using Roxio.
I am loathe to shell out huge amounts to one of these firms that advertise, with no guarantee that I'll be able to recover anything. I'd be grateful for any thought.

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