The offline Titan Quest Equipment Database was brought to the attention of the English-speaking community on Unofficial Titan Quest Forums by the user Tonatos from titanquest.net and forums.ag.ru, which has a Titan Quest - Immortal Throne thread (originally in russian but here translated by google to english).
This tool lists most items from Titan Quest in the convenient form of a Windows Help file (.chm format) and was possibly (needing confirmation) developed by the user Obi_van which is originally from the forums.ag.ru community.
The original .chm file was extended by vorbis from the titanquest.net community and sports now all Monster Infrequents from all difficulties, the MasteriesCalc 0.2 and OccultulatorRC2. The original 1.17.2 version was replaced by the Extended Version 1.0.
The tool can be downloaded here: Download Offline Titan Quest Equipment Database Extended Version 1.0
If the link doesn't work, you can always check out the downloads available on the original post