repeat text

Well Google Images is a good place but I find alot of sprites just by googling something like "Final Fantasy VIII portraits, or Final Fantasy V Portraits..etc.
If you can find one, then just do the above steps to make them 40x40 and 16 colors..
And yes, there's always the option to make your very own portraits.
FF3SE is one of the options you have, but with portraits, it's a little more flexible - you can use programs like MS Paint and Irfan View to make your portraits. It's actually recommended.
But good luck with it all man :p