There's probably a link to this somewhere, but I have 4 of those "Ian Hammell" novels on the shelf next to me so...
The first three had a copyright of Bill Fawcett and Associates and weren't bad as mass-market fantasy novels go, but the first three really didn't have the Shadow World feel. I don't regret buying them though. The fourth one I love and even have multiple copies.
Book 1: Shadow World: The Burning Goddess
A tale of adventure at the Lost City of Tarek Nev, on the isle of Aranmor in Jaiman from the Demons of the Burning Night module.
Book 2: Shadow World: Clock Strikes Sword
Two warring nations on a shared island need to unite against a common enemy. Each society has a distinct form of magic. Frankly, I don't remember any real connection the Kulthea at all in this one. It's just a decent fantasy story.
Book 3: Shadow World: City of Assassins
This picks up with the same main characters as the first book and is set in Sel-kai. I don't remember much but the back cover says the Dragonlords are kidnapping victims and using them to open portals in some plan to take over the world. A highly alternate version of Kuthea at best.
Book 4: Shadow World: Stormriders
This is actually a reprint of the first and only SW novel published by ICE itself back in 1990. The copyright is for the original author Roxanne Longstreet. It's set in NW Jaiman in the region detailed by the Quellbourne, Land of the Silver Mist module. Written so long ago, it's version of reality is a little different than Terry's timeline, but it has a good "Shadow World feel" especially compared to the other three. Terry has given this one a sort of "quasi-canon" status. Don't rely on it's details, but the overall representation of the world is pretty good.
If you want Stormriders I recommend the ICE version if you can find it because the cover art is actually relevant to the contents. ICE might even have some in stock but I haven't checked in quite a while. On the other hand they didn't actually change the text in any significant way so the ACE book is good too.
I think there were only 4 of them but if there were more I would love to know just to satisfy my collector instinct. They were published between 1994 and 1996.