Those are generally core on him. Wit's End is excellent as a sole offensive item. From there he likes just stacking up resists and CDR. Spamming bite lets him put out a good amount of damage without building it, also gives him a ton of health.
Madred's Bloodrazor doesn't fit in his build too well, lategame item maybe. I get it after my core if I'm really rolling to make him impossible to deal with. If their carries don't build QSS it is rather deadly, adds 200 + 20% max health damage to his ultimate.
"Happiness is nature's way of telling human resources you're overpaid." - Catbert
Spirit Visage is kind of meeeh. Glacial Shroud and Wit's End provide enormous stats that are all perfect for WW. Merc's is usually best boots, since you need to dive through the team and such things. Get Frozen Heart and whatnot after. Randuin's is cool, and so is Banshee's.
*waits until someone says something funny to quote*