They only need to be unique for a page though so you could have something like <div id="index_page_sponsor_link1"> and have a way of addressing style instructions to the first sponsor link block on your index page anytime you felt you needed such a thing.
I have only built a few free sites and at this point it still takes a few weeks to do so. Looking at the thread
How Many Free Sites Do You Submit.... my view of building them efficiently seems to be early on the learning curve. If there are any reasons why LL owners wouldn't like them I woud be interested in knowing.