Some great online resources for recipes and cooking tips are Epicurious - www.epicurious.com, The Food Network - www.foodnetwork.com and www.foodgawker.com. On all of these sites, you can search for a recipe or an ingredient (if you have a ton of potatoes, for example, just search “potato” and you can find a ton of options).

I found a couple of great, classic green bean casserole recipes on these sites. You can see in their ingredient lists that many recipes call for the same ingredients. My favorite thing to do when cooking is to look up a few different recipes for the same dish as a starting point, then vary them depending on what ingredients I have on hand, or what flavors I’m in the mood for. This also helped me be more comfortable in the kitchen!

Campbell’s Green Bean Casserole recipe, from http://www.foodnetwork.com/recipes/green-bean-casserole-recipe2/index.html

Ingredients
2 cans (10 3/4 ounces each) Campbell's® Condensed Cream of Mushroom Soup (Regular or 98% Fat Free)
1 cup milk
2 teaspoons soy sauce
1/4 teaspoon ground black pepper
8 cups cooked cut green beans
2 2/3 cups French's® French Fried Onions
Directions
Stir the soup, milk, soy sauce, black pepper, beans and 1 1/3 cups onions in a 3-quart casserole.
Bake at 350 degrees F for 25 minutes or until the bean mixture is hot and bubbling. Stir the bean mixture. Sprinkle with the remaining onions.
Bake for 5 minutes or until the onions are golden brown.
Tips:
Use 2 bags (16 to 20 ounces each) frozen green beans, 4 packages (9 ounces each) frozen green beans, 4 cans (about 16 ounces each) green beans or about 3 pounds fresh green beans for this recipe.
To add crunch, add 1/2 cup sliced almonds to the onion topping.
For bacon lovers, add 4 slices bacon, cooked and crumbled, to the bean mixture.
To add a festive touch, add 1/2 cup chopped red pepper with the soup.
For cheese lovers, stir in 1 cup shredded cheddar cheese with the soup. Omit the soy sauce. Sprinkle with an additional 1/2 cup cheddar cheese when adding the remaining onions.
For Golden Green Bean Casserole, substitute Campbell's® Condensed Golden Mushroom Soup for the Cream of Mushroom Soup. Omit the soy sauce. Stir in 1/2 cup chopped red pepper with the green beans.

The Joy of Cooking recipes for Green Bean Casserole, courtesy of http://www.epicurious.com/recipes/food/views/Green-Bean-Casserole-360809
Green Bean Casserole I:
1 pound green beans
One 10 3/4-ounce can condensed cream of tomato soup
3 tablespoons prepared horseradish
1 teaspoon Worcestershire sauce
1/4 teaspoon salt
1/4 teaspoon paprika

Au Gratin:
Dry bread crumbs
(Paprika—about 1/2 teaspoon per cup)
Dots of butter
Grated Cheddar, Romano, or Parmesan

Green Bean Casserole II:
1 pound green beans
Butter for greasing baking dish
3/4 cup milk
One 10 3/4-ounce can condensed cream of mushroom soup
2/3 cup canned French-fried onion rings, plus additional 1/2 cup
Salt and black pepper to taste

preparation
Green Bean Casserole I:
Preheat the oven to 350°F. Wash and trim the stem ends from green beans. Place in a greased 8 x 8 x 2-inch baking dish.
In a medium bowl, mix cream of tomato soup, horseradish, Worcestershire sauce, salt, and paprika. Pour over beans and bake, covered, about 1 hour
Top with au gratin ingredients, below. Heat in broiler until the cheese is melted.
Au Gratin:
Completely cover the food with bread crumbs paprika, butter and cheese.
Place the dish in a preheated 350°F oven or under the broiler 5 inches below the source of heat, and broil until a glazed golden crust is created.
Green Bean Casserole II:
Preheat the oven to 350°F. Wash and trim the stem ends from green beans. Place in a buttered baking dish.
Mix milk, cream of mushroom soup, 2/3 cup canned French-fried onion rings, and salt and black pepper to taste
Pour over beans and bake, uncovered, about 30 minutes.
Sprinkle with 1/2 cup canned French-fried onion rings.
Bake until browned, 5 to 10 minutes.