This report is a follow up of a previous one  introducing users to computational grid data processing.
Computational grids used for the tests are supplied by High Energy Physics laboratories in Italy (INFN) and at CERN taking advantage of the economical and technical efforts and infrastrucures available to the LHC experiments.
The present setup allows usage of two different grid tools: the European Data Grid middleware (EDG2) and the LHC common environment (LCG-1) supported by CERN and INFN grids. Main concepts and commands are shared by both grid tools and users are slightly involved in the different details.
In Section 12 are listed the site resources of the INFN and CERN application testbed used for the very first test approaches. The table is intended only to keep track of the various UIs used by the author for tests, and has only an historical meaning.
At present INFN grid is becomimg a real service based on LCG-1 and named GRID-IT with an official site at http://grid-it.cnaf.infn.it/, thus every enquiry about the INFN grid must be addressed to the official site.
The document is addressed to users with previous grid experience and knowledge of grid basic concepts and terminology.