Hail good citizen of Norrath!
While I have not played a warrior I have had the chance to adventure besides many of P99's top warriors. Warrior can be one of the most expensive classes to gear out if you really want to. Here are the humble suggestions of a monk.
At higher levels the only way warriors keep agro are from procing weapons, but most of the good weapons don't proc until 45+ or 51+...
1) Weapons - get a set on Blood Points
http://wiki.project1999.com/Blood_Point or a set of
http://wiki.project1999.com/Lamentation.
2) Cobalt wont really help you tank but it offers some very nice utility. The legs give you an invis and the bracers let you shrink yourself (good for large classes). I would think getting haste and a fungi would be light years better than Cobalt if you are having to pick.
If I was you I would buy a set of blood points, fungi, FBSS and then start filling in with as much HP/Stam/Dex gear as you can get your hands on.