Find Artus Cimber

Sirac of Suzail mentioned his father Artus Cimber who hasn't been seen in some time and is protected by Divination magic.

He also gave the party some Rose Tinted Spectacles which he says may be the only way to find him.

Sirac describes him as rough looking, ruggedly handsome. Sirac kind of hates him, but he knows that Artus is in possession of a number of magical items as well as the ring of winter.

Probably worth looking into...

Jarlaxle has a device from some giants that can use some blood to locate the nearest creature of the same bloodline.... this might help.

The winter palace may also be worth looking into, since Artus's magic ring has to do with winter as well.