I once found a spider statuette in George's back room, but have not seen a frog one before getting to Ars magicana (sold by Kistandalius).
The quality of an item is somewhat dependent on your character level (the higher the level, the more likely stats will be in the upper range for that item), so getting the ring or dragon belt right away may result in them being of poor quality. In trying to finish at the lowest possible character level, Ariana re-loaded at about level 5 to try to get a holy sword with Frost, but failed. Waiting until level 9 or 10, she was able to get a good quality sword much easier.
Finnigan's magic lockpicks would be handy early in the game, if you get to Verdistis.
