I have a request for a Twilight Cake, They want one cake laying flat and one standing upright. I really dont know where to begin. Should I Layer the cake with 7x4 inch pieces layer frosting layer frosting stacked up to 10" tall and just secure it with a few dowel rods? Maybe someone else has experience with a upright cakes and can provide some insight. PLEASE HELP!   THANKS!

For tall, flat structures like that, I stack and dowel as you mentioned with cake boards every 4" or so of cake.  I  get DH to cut and drill a custom cake board for me so that the dowels (or threaded rods) are firmly secured to the board and then put the cake down over the dowels.  Don't forget to mark and drill the cake boards before putting cake on them.....