the character lcd modules on the site you reference are
not serial devices. they require either 7 or 11 i/o lines. with seven i/o lines they transfer 4 bits at a time and require two transfers to send a single byte.
if memory serves the i/o lines are ...
e - which strobes the data into or out of the lcd
r/s - which tells the lcd whether you are sending data or a command
r/w - which tells the lcd whether you are performing a read or a write operation
d1 - data line 1
d2 - data line 2
d3 - data line 3
d4 - data line 4
with 11 i/o lines, you use four more data lines and transfer data a whole byte at a time.
you also need to supple 5v, ground, and connect a 10k pot to control the display contrast. with a backlit display you also need to supply power for the backlight. the protocol to get these devices configured is a little baroque, but not too bad.
the displays use a hitachi 44780controller, which is explained pretty well
here .