Giant Space Hamsters are a Spelljammer creation, and were never offically converted from ADnD to 3e.
You may want to try the Creature Catalog/conversion section of the forums, where alot of classic creatures have been updated.
Here is a link for a Spelljammer site shattered fractine that has 3e (not 3.5 I thin) stat block coverted from 2nd edition. I cannot vouch for the coversions accuracy.
I have a memory that these things might have originally appeared in the context of a Dragon magazine April Fool's issue from a long time ago (under issue 100).
In the Spelljammer setting these giant hamsters ran in enormous hamster wheels attached to gnomish vessels and helped propel them through space.... I believe their dung was also used to fuel the vessel.
(I'm sure that where giant space hamsters are concerned there is no "right" forum, but this one will do just fine. )
I love giant space hamsters (and their April-issue offshoots, like fire breathing phase doppelganger giant space hamsters). Secretly, I've always wanted to kill a PC with one. Would they even want to be raised?
[size=-2]I guess it's not a secret anymore...oops.[/size]