In your backyard, self catered.
Now, lets get serious.
Where are yu in LA?
What do you envisions, at least want? A hall, a reception place? A ceremony and reception place? how many guests? theme? Catered or non? Breakfast, cocktail hour only, cocktail hour and dinner? Buffet or plated or just passed fancy snacks? traditional cake? Cupcake Cake? Candy bar?
Morning, afternoon or evening?
Your budget can go all over, depending upon what you want. weddings are too variable for just a blanket answer.
Generally, those held at a local park, golf course, small event hall are the least expensive, and cheaper if you do your own planning and easy things, like announcements and invites from kits at Micheal's. Most places will cater, from El Pollo Loco to Providence and all in between. Some places, Like Descanso Gardens, insist you use only their caterers. Is it a church ceremony followed by a separate reception, or are you hoping to do the ceremony and reception all in one place?
Step back, do some basic brainstorming and planning, and come back to us with more info!