East side of map looks like where I'd head off in search of Yagluth. Load up a ship with materials for base and go!
When you come to swamp keep going and when you get to mistlands turn around. Stay in that plains range.

edit: no I didn't look up seed - just my experience with exploring. My 12+playthroughs... I'll agree that Yag needs more of the vegvisir (sp?) things. Look for the stonehenge type sites.