The list of registered substances is updated by ECHA constantly. You can see if the substance was registered, what kind of registration it has passed (full dossier, intermediate, transported isolated intermediate) and if the dossier was published by ECHA (as non-confidential information from successful dossiers will be published in the year 2010).

You may download the list of registered substances here in .xls file and then use function "Find" in Excel to find quickly your substance - go to download page at ECHA website.