I have just placed an order with Good Rich Furniture. They are at Jatujak, Soi 5, Zone B. I met a young man there who was quite professional and friendly. They do made to order furniture and I'm pretty sure coffee and side tables would be right up their street. As I don't have my order yet, I can only comment on quality of communication on which they score very highly. They do have some furniture on display. If you want to know more details please visit here https://www.interiorsecrets.com.au/collections/coffee-tables
the ones I have made are usually 18" tall 18" wide at the top and 36" long at the top. Overhangs will generally be about3" on the ends and 2" on the faces If I make them longer than 36? I usually make the tops 1/2 the length. But thats not something firm. I make pieces based on what I have for wood. Let the wood talk to you and tell you the top dimensions ( also the room its going in mingh chime in a bit too) The height is always going to be dictated by the seating surcfaces