Alan,
there is a boat age synopsis on the main website;
http://wayfarer.org.uk/index.php?option=com_content&task=view&id=26&Itemid=51
Obtaining a manual as such is a more interesting question. The most comprehensive guide would be the Wayfarer Book – available from the Secretary;
http://wayfarer.org.uk/index.php?option=com_content&task=blogcategory&id=27&Itemid=98
If you have a specific point on your boat that you are looking for advice on I would suggest you post it under technical.