Toto makes a nice one at comfort height.

Also Kohler and American std toilets with comfort height toilets that are 17"-18" seat ht.

If the whole family is tall, you might want to check out a wall mounted unit if your wall can accommodate the depth.
Toto Acquia or Duravit Starck Series are two very nice ones.

If you are doing a wallmount toilet, much depends on the height of the water chassis you install that is inbuilt into the wall. In Europe we use Geberit (not sure what is used in the US) and there are different types that allow a range of height of toilet.

Basically you need to determine at what height you are comfortable sitting and then explain that to the plumber. He can then adjust the wallmount unit to ensure you have that height.