Peter McCracken's site is essentially a collection of categorised links, but the author is a professional librarian and the organisation of the links is well thought out and very helpful. The structure is there, but it seems to be taking some time to add the links ! One day this site may be the essential first visit for people searching the Internet for original maritime history information. This site does include an index of ships named in the major books published on maritime history, guides to photographic and archive collections and lists of international and regional sites.
 

Lars Bruzelius's site is extensive, and unlike Peter McCracken's site includes, as well as links, a great deal of original information. It is an extensive and detailed site, and well worth a visit if you are researching areas of significant international  maritime history. The site has been established for several years and includes some non-working web links. Its own illustrations (ship models and some ship photos) are of not of the best quality, but the detailed information on famous sailing ships and maritime matters is extraordinary.
 

This is a very highly regarded site that covers all aspects of sailing and maritime history. It includes some original material but it also has extensive, categorised links. It is always up-to-date, so, whatever your area of interest, I strongly recommend a visit.
 

This site  is a kind of potpourri on maritime matters. It includes details of modern replica ships, particularly schooners,  and general information on sailing ships and maritime history.  It includes a variety of links to maritime history and sailing sites, and also advertises sailing and history books.
 

This is an English site dedicated largely to naval history, particularly the Royal Navy. It includes some excellent articles on naval history, and a section dedicated to Nelson and his era. There aren't many links, but if your interest is primarily naval history from the 18th and 19th Century, then the original material on this site should be of great interest.
 

A great source for sailing ship photographs, with a simple to use Search facility.  As an example of the quantity of data available, this gave over over 2000 ( two thousand !!) results for the word "barque", each with a photograph, and about 100-200 for brig, schooner etc. There are photos of the Furness ships  Mary Barrow and the Euterpe, and also the other Euterpe (Star of India), built in the Isle of Man. An excellent site ! 
 

The National Maritime Museum PORT facilty is a searchable database of online maritime history resources. The lists are rather bloated with sites from commercial organisations that are more to do with 'maritime present' than 'maritime past'. However, the database has increased rapidly and at least all the sites are accurately described and indexed. Worth a look if you have some time.
 

Canadian site dedicated to maritime conservation and education. Links to a range of maritime history sites, many based in North America.
 

Sites which cover aspects of the maritime history of the North West of England and the Isle of Man, also North Wales, are listed on a separate links page. Click on the ship to go there.