Here is a list of resources that may be useful to you.
Please note that the Welsh Language Tribunal is not responsible for the contents or reliability of the linked websites and does not necessarily endorse the views expressed within them. Listing shall not be taken as endorsement of any kind. We cannot guarantee that these links will work all of the time and we have no control over availability of the linked pages.
Welsh Language Commissioner (external link)
Welsh Language (Wales) Measure 2011 (external link)