Ed: The following is from a post by Joseph Hewitt in gearhead_dev.
In order to recover the Argoseyer you're going to need to find three items: the Fuel Rod, the Code Disk, and the Argoseyer itself. You'll also need to find the Old City Key, and will need to know the Investigation, Code Breaking, and Bio Technology skills.
The Fuel Rod can be found in the Ziggurat Downspiral, which can be entered from the fourth floor of the Ziggurat. No special requirements to getting this one other than being able to survive the poisonous swamp + other hazards of the dead zone.
If you travel to the top floor of the Ziggurat you'll be able to access a computer which will give you more information about the Argoseyer, and also about Ladon.
The Code Disk is in Wujung. You've probably heard the rumor that Wujung was built on top of a ruined city... well, you'll have to go deep into the undercity to locate the disk. The entrance is in the university area in a locked building, but once you get down to 60m you'll find a locked grate and won't be able to go further. This is where the Old City Key comes in.
You may have heard rumors that Wujung Hospital is the oldest building in town. Go there and search... You'll find a trapdoor leading down into a different section of the undercity. The trapdoor is extremely well hidden so it will help to have a very good Investigation skill. Go down, get the key, then return to the other entrance and get the disk.
Dataslycer: Oddly, you only need to pick up the key to be able to go past the disk floor so it doesn't matter if you drop or sell it afterwards. The Argoseyer itself is located in an ancient factory-fortress south of where the Cesar Citysmasher was defeated--that's in modern-day Kist. Search the houses there for a trap door. You'll discover a cave... In the cave is a partially melted skeleton. Try using your clue skills on it for a number of humorous messages.
In order to get to the actual ruins, you'll have to pass a Sentinel robot. Unlike the Sentinel guarding BioCorp's mesa lab there's no way past this one without fighting. Fortunately the Sentinel's aim isn't too good but one hit from any of its weapons will most likely kill you.
Once you've gotten past the Sentinel, you'll find yourself in an ancient factory. There are plenty of robots and synths here; make sure your personal combat skills are extremely good before even attempting this dive. If you didn't manage to kill the Sentinel before coming down you may not want to be going back up by the stairs.
On the second floor there doesn't appear to be a way down, but you will find an old machine. Use your Investigation skill on it and you should locate an attached keyboard. Use your Code Breaking skill on that and you'll hear a gate opening... The stairway down to the next level has been revealed.
Monsters on the third level are really tough, and you may even encounter more Sentinels as wandering monsters. The Argoseyer is buried in debris... A good Investigation skill will help you to spot it when you get near it. Insert the Fuel Rod and the Code Disk into the machine and it immediately comes back to life.
(Editor: You will need to go to any FedTer town and ask the bus dispatcher to deliver the Argoseyer to you; you won't be riding in it when you are put into the World Map)
Why will you need to know Bio Technology? Because the Argoseyer is a biotechnological construct, and if you damage it there's no-one else who's going to be able to repair it.
Let me know how you like using the Argoseyer after you get it...