Wedding cake 411 needed

The Yellow pagesfind a good wedding cake decorator

Step 1: Which is most important, taste or appearance?

Step 2: Wedding color(s)?

Step 3: Tiered, sheet, or cupcakes?

Step 4: How large, i.e. to serve how many?

Now you have the basic information to start looking and asking more questions.

You should do at least a  smaller version first.

Also practice rolling fondant if you haven't worked with it before.

I did my daughter's wedding cake - never done one before, though i bake a lot.  Searching many websites i ended up being recommended the Cake Bible by many people, and indeed it was the most useful of all.  I highly recommend you buy it.  She explains every detail of the baking (esp the differences in baking a very large cake - like 12 inch diameter) and how the recipe has to change, she has wonderful recipes, and also the structural construction aspects. 

I made, on my daughter's request, a fudge cake with dark chocolate raspberry ganache, filling and white chocolate cream cheese butter cream as a crumb coat (under the fondant) - a fondant frosting. I did it in 100 degree heat without air conditioning, freezing layers as i made them, constructing it at the last minute and transporting it to the wedding place in a huge box, where they had a fridge. 

It was 6 layers, three tiers. 

Her description is very good and you can't go wrong.  Make a small version to try first.  She also has a website and you can ask questions and she'll answer (I did and she did).