I don't know if there is something else you can use if you don't have a special madeleine pan:

MADELEINES

2 lemons
5 eggs
1 cup superfine (caster) sugar
2 cups flour
2 teaspoons baking powder
salt
1 cup melted butter

Preheat the oven to 450F. Finely grate the rind from the lemons. Beat the eggs, with the sugar, then stir in the flour. Add the baking powder, a pinch of salt, and the lemon rind and mix well. Add the butter and stir until well blended. Butter 2 or 3 madeleine trays. Sprinkle with flour and shake out any excess. Fill each madeleine mold with the batter and leave to stand for 10 minutes. Bake for 10 minutes. Remove the trays from the oven and unmold the madeleines immediately.