Jon over at Gamebanshee shared with us the spell and equipment databases they have have hosted on their site. These databases cover all 5,922 items within Oblivion, Shivering Isles, and all DLC, as well as all 430 spells.
What’s most impressive to me is how comprehensive the search filters are. For searching spells alone, there are eight separate filters to use, as well as the ability to filter the search down to any of the 89 different spell effects. As a relative newbie to the game (thankfully I just got my 360 back), the simplicity of both of these search engines is definitely something I can see using. The filters even let you know what can be found in Oblivion, Shivering Isles, and all the other add ons and plug-ins.