I love muffalettas from New Orleans, but since I live in San Diego I
like to make my own. I have a great recipe and can find all the
necessary ingredients EXCEPT a 10 inch round Italian loaf of bread.
Here's a picture of a muffaletta:
http://www.ragingmain.com/html_nola/vo-ss-09.htm -- I've checked a
couple bakeries in Little Italy and Bread & Cie in Hillcrest, but
nobody seems to carry it. I'd prefer to buy from a local bakery
(fresh!) rather than mail order.

Never heard of muffaletta. It looks like salami and cheese sandwich on the picture.
Would it hurt if you make it with rectangular loaf of bread ? Is the
round shape a must? Let's put it in another prospective - would you
eat square muffaletta if you haven't eaten for 3 days?

I'd probably eat muffaletta either which way (and have made them with
a variety of artisan breads of different shapes and sizes), however,
I'd prefer the big round bun which is used in the Central Grocery Co.
(New Orleans), the attributed originator of the muffaletta.

this makes sense.

It's made on round bread to keep the edges from burning and to give it
an even toasted crust because of the amount of ingredients on it.

Try to convince one of the local bakeries to bake a couple for you.

Thanks for your comment - my experience, however, is that it is not toasted.

I am dying to eat muffaletta myself.  First, you need to get some
good, hearty, French Bread, rolls, or whatever you prefer.  Find the
finest salami (such as sopressata) and some good mozzarella.  For the
muffaletta dressing, check on the Food Network site for specifics. 
You can make your own version with chopped up greek, black, and green
olives to your liking, some pickled peppers, onions, vinegar, some
oil...all to taste.  I am thinking the authentic version may have
carrots.  I will check this out and check back to you.

http://www.foodnetwork.com/food/recipes/recipe/0,,FOOD_9936_29541,00.html

Here's your link to an authentic "olive salad", basically what is used
in muffaletta.

Enjoy! (: