It depends on the type of cooking. Take a look at this site: Egg substitutes - Egg Replacer - Baking Substitute - Egg Allergies - Ener-G Egg Replacer Tom
There are many vegan cookbooks out there. Eggs perform a critical function in most of the dishes where they are used, so simply leaving them out can be disastrous. You could use one of the substitutes Tom suggests, but my recommendation would be to browse your local bookstore for a good vegan cookbook or several. Recipes that are designed to be vegan from scratch are likely to do better (especially for a beginner) than conventional recipes with egg substitutes. Rae Vynn might have some good vegan muffin recipes. Actually, I'd be very surprised if she does not. I don't bake muffins. I lack the self control to refrain from eating them all in one sitting.