Mike Davies just came out with his book 'Essex and Suffolk Boatyards & Boat Builders'.
Highly recommended. And so well written that, even if you aren't like me and have a special interest in this subject, it is worth reading as well as being an important historical document. Most of the establishments described no longer exist. (Among other factors, it seems that waterfront development in the UK, (as in the US) has made businesses such as these economically unviable). So far, I believe you can only purchase this book from Mike Directly. The address of his site is: www.eastangliaboatbuilders.co.uk