Once you have decided what type of wedding cake you want and have at least a general idea of the design you want, it's time to begin visiting bakeries. When you do, be sure to taste their wedding cake samples. Don't let yourself be swayed by talk about the ingredients they use, taste their wedding cake samples and decide for yourself because, frankly, your guests aren't going to know if your wedding cake was made from flour imported from a water powered mill on the south bank of a coastal stream in upper Scotland. All they are going to know is whether or not your wedding cake tastes good and looks good. So let taste (and artistry) be your gauge in choosing your bakery to provide your cake.
Look at the pictures that the bakery has of past wedding cakes to decide if the bakery is even capable of doing what you have in mind. Toward this end, it is helpful to have a picture in hand to show the decorator what you want, that way they will know what part of their wedding cake portfolio to show you (though you might want to peruse the entire thing just in case you see a wedding cake that you like even better).
Take the time to talk to the decorator and try to develop a rapport. You may not have much contact with them once you place your order but it is important that you are certain that they have understood and are going to create the wedding cake that you want rather than some fantasy from their mind (which might or might not reflect your tastes and values).
To avoid surprises on your wedding day, ask your cake decorator how much time they need to set up the cake. In most cases they will need to set up one to two hours prior to the time the guests will begin arriving, but that all depends on the wedding cake you order and the other cakes your decorator has to deliver that same day. This will mean that your wedding cake location will need to already be established (in a highly visible but safe area - wedding cakes don't like fireplaces, children, and high traffic areas if your table is the least bit wobbly).
Likewise, ask about their policy for putting fresh flowers on the wedding cake, if your wedding cake design includes fresh flowers. Some cake decorators are very picky and will not allow the florist to place flowers on their cake (in fairness, in some cases this has come out of a bad experience where a bride wasn't happy with the cake after a florist placed flowers on the wedding cake). Of course, if the cake decorator is going to put the flowers on the cake, the flowers will need to be in the reception hall when the cake is delivered. This way you can ensure that the flowers on the wedding cake match the rest of the flowers in your wedding and actually do get placed on the cake.
Also, ask about their policy regarding cake flavors. Some bakeries charge extra for a variety of flavors while others do not. Check also on delivery charges for your wedding cake as these too can vary greatly. If your wedding is close, delivery may be free, but if much travel is required expect to pay a delivery fee. Most bakeries will require, along with your initial deposit, a deposit for the cake plates and pillars. This deposit is usually returned as long as the plates and pillars are returned by an agreed upon time.
Likewise, if you want the bakery to match a color in your color scheme (such as the color of the bridesmaids dress); bring a swatch of the colored fabric to the initial consultation with your cake decorator. Her idea of mauve and your idea are probably not exactly the same so unless you want to run the risk of having colors that clash, provide a swatch. Be warned, though, icing has to be colored by hand so trying to match a color will be time consuming, which will mean more expense to you.
If you want that elegant wedding cake but money is an issue consider a simpler design. A simple cake with ribbon or roses can look beautiful. Likewise, consider ordering a smaller wedding cake with plain sheet cakes to make up the difference in servings. The sheet cakes can be held behind the scenes and used to supplement the wedding cake and will hold down your cost tremendously.