Here are some things that you might find helpful when ordering a cake.  Below is a link to a printable order form and some options that are available for size, cake and icing flavors.  
ORDER FORM
Cake Flavors

White
Chocolate
Marble
Combination
Carrot
Yellow
Italian Creme
 Fillings

Strawberry
Raspberry
Lemon
Peach
Pineapple
Chocolate
Dark Chocolate Mousse'
Bavarian Creme
Icing flavors

Buttercream
Chocolate
Cream Cheese
Whipped buttercream
Dark Chocolate (Ganosh)
Fondant
  The number of slices per cake are based on a 2" by 2" piece of cake.  When choosing a size it is always better to round up when estimating the amount of cake you will need.

Sizes
Rectangular Quarter sheets:             Slices of cake:                          Round:                    Slices of cake:
7x11                                                       28                                     6"                                  12
9x13                                                       45                                     8"                                  20          
                                                                                                      9"                                 24
Half Sheets                                                                                   10"                                28
11x15                                                     60                                   12"                                40 
12x18                                                     72

Full Sheets are also available 
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