Recently completed a month-long trip around Thailand and thought these sites might be helpful for others (they sure were to us) Not only single sites but I found all in just one directory site. https://travelsites.com/ Fantastic lists of best beaches, best hotels, and best attractions insurance sites were also very helpful.
Had never heard of this website before but looks like it has tons of information for trains all over Southeast Asia and the world. It was helpful for finding hotels and reading reviews. A little hard to navigate but there's good info in there if you have the patience to find it.