Generate list from table column

Hello all

Hope someone can help, I have a table that list products a shop has in stock
one column has the make the other has the model and another has the price.
What I want to be able to do is have a search on the front page that
customer can select the make they want to search for and just search for
that make like a normal search. But I only want the customer to be able to
select from the make's the shop has in stock. So I need the make search list
to only select the make's the shop has in stock. The problem I am having is
that the make column in the table has multiple entries the same so how do I
filter this column to only select each make once.

If anyone can help please post.

Cheers Pete Thompson