Steadvex, what software do you want?
Only engines and gearboxes? Then you can use any OBD2/EOBD scanner on a PC or handheld but expect problems.
The European Union decided that not all vehicles had to be compliant in the same year. They started with petrol cars. Then a few years later they started with the diesels. However, the last diesels were only to be compliant on 1st january 2007 (Yeah, that's right, last year).
Here's a quote from the EC document:
8.1.1. Petrol fuelled engines
With effect from 1 January 2000 for new types and from 1 January 2001 for all types, vehicles of category M1 - except vehicles the maximum mass of which exceeds 2500 kg - and vehicles of category N1 class I, must be fitted with an OBD system for emission control in accordance with Annex XI.
With effect from 1 January 2001 for new types and from 1 January 2002 for all types, vehicles of category N1 classes II and III and vehicles of category M1, the maximum mass of which exceeds 2500 kg, must be fitted with an OBD system for emission control in accordance with Annex XI.
8.1.2. LPG and natural gas fuelled vehicles
With effect from 1 January 2003 for new types and from 1 January 2004 for all types, vehicles of category M1 - except vehicles the maximum mass of which exceeds 2500 kg - and vehicles of category N1 class I, running permanently or part-time on either LPG or natural gas fuel, must be fitted with an OBD system for emission control in accordance with Annex XI.
With effect from 1 January 2006 for new types and from 1 January 2007 for all types, vehicles of category N1 classes II and III and vehicles of category M1, the maximum mass of which exceeds 2500 kg, running permanently or part-time on either LPG or natural gas fuel, must be fitted with an OBD system for emission control in accordance with Annex XI.".
8.2. Vehicles with compression-ignition engines
Vehicles of category M1, except
- vehicles designed to carry more than six occupants including the driver,
- vehicles whose maximum mass exceeds 2500 kg,
from 1 January 2003 for new types and from 1 January 2004 for all types, must be fitted with an on-board diagnostic (OBD) system for emission control in accordance with Annex XI.
Where new types of compression-ignition engined vehicles entering into service prior to this date are fitted with an OBD system, the provisions of sections 6.5.3 to 6.5.3.6 of Annex XI, Appendix 1, are applicable.
8.3. Vehicles with compression-ignition engines exempt from Section 8.2
From 1 January 2005 for new types and from 1 January 2006 for all types, vehicles of category M1 exempted by Section 8.2, except vehicles of category M1 equipped with compression-ignition engines and the maximum mass of which exceeds 2500 kg, and vehicles in category N1 class 1 equipped with compression-ignition engines, must be fitted with on-board diagnostic (OBD) systems for emission control in accordance with Annex XI.
From 1 January 2006 for new types and 1 January 2007 for all types, vehicles in category N1, classes II and III equipped with compression-ignition engines and vehicles of category M1 equipped with compression-ignition engines and the maximum mass of which exceeds 2500 kg, must be fitted with on-board diagnostic (OBD) systems for emission control in accordance with Annex XI.
The full documents can be found here:
http://eur-lex.europa.eu/LexUriServ/...9L0102:EN:HTML
http://eur-lex.europa.eu/LexUriServ/...1L0001:EN:HTML
Now if you want to do more than just engines, you need some manufacturer specific software or scanner.
Excellent PC-software is available for VW/Audi from Rosstech an for Opel there's the program OP-COM (or VAUX-COM in the UK).
There's software for other makes too, but the opions on th quality of these vary greatly.