If you usually make your own pound cake, I would just take the recipe you normally use and modify it. It is usually called pound cake because it has a pound of butter. I suggest using half a pound of light butter and half a pound of fat free cream cheese instead of one pound of full fat butter. If it calls for eggs, leave out the yolks. That should give you a good start. If not, here is a site that might help:
Does anyone have a lower cal/fat version of a basic pound cake?
I have this fabulous summer recipe that I eat all the time during the summer, sometimes in place of dinner and the worse ingredient in it is the chunks of pound cake. So, I am starting now to try to get around those downfalls. If only I can find a good pound cake it will be a SP appropriate recipe.