What size table do I need to seat 14 people?

probly a 10-15 foot by 5-7 feet table maybe be a little smaller

I sell furniture. The BIGGEST table I have seen seats twelve, and you will spend THOUSANDS to get something this size. Only a conference table will seat twenty. Really--rent some folding tables. This is a once-a-year event. The table would have to be at least (6 x 3 = 18) feet long (two on the ends, six on each side, minimum 3' spacing).

You'd have to find a table that has 'leafs' - there are oak tables that usually have them, and they open to a length of at least 6 feet. They fold into the table, or you can take them out, making the table smaller for everyday use. That way you don't have to have a hulking great monster in your dining room when you don't want it. You can try flea markets, specialty furniture stores where if they don't have them in stock they can make one.

3 - 8 ft by 4 ft folding tables, remove the other table form a u shape with the new ones, seat inside and out sides of the tables, just rent them,

If you go to a party supply/equipment company that rents tables, you can rent two "ten-top" tables. They are 6 foot wide round tables that seat 10 people each. THat way you can seat everyone and not spend a fortune to do it. They shouldn't cost much to rent, especially if you pick them up and return them yourself (you'll need a truck or large van to do that).

you could just go to the furniture store where you want to purchase that table and even if they do not have that size they should be able to tell you the size that you are looking for.