Roccomania now have a database for which you can list the mods and costs for your car, a rating system for each item and more this is the only one in the UK and at least worth a look should you own one of volkswagens fogotten coupes
The UK's First Scirocco Tuning and Mod Database
http://members.lycos.co.uk/norice/index.php?s=&act=Garagehave a gander anyway..