What is a TBX File Type?
To create a TBX file, navigate to the database (a storage structure used by ArcGIS to manage and edit GIS data) or to the folder in the file "Catalog" window where you want the toolbox to be created, right-click-on the database or folder, and select New → Toolbox. You can leave the default name as Toolbox or enter a new name. You can also create a toolbox by clicking on the icons of the toolbox at the time of application; registration d' a new model in ModelBuilder.
You can browse through the toolboxes by searching the file for their names, Search "window or using the file Catalog" or "ArcToolbox" window. Some of the TBX systems shipped with ArcGIS for Desktop are: 3D analysis, mapping tools, conversion tools, data management tools, geo-coding tools, simulation tools, d'tools, spatial analysis and d'tools; follow-up analysis.
By default, TBX files are saved in the following location.
Documents and settings\ [user name; user]\ Application\ ESRI\ ArcToolbox\ My Toolboxes\ My Toolboxes.