Here is a great tip that I learned when attempting to fill my large garden beds with dirt last week.  If you've ever had to purchase potting soil or topsoil for your garden you know that a bag (1 cu. ft.) of dirt is anywhere from $3 to $8 a bag.  If you have a large garden bed to fill that is going to be expensive!!!  You want good dirt in your garden bed though so here is something you may try where you live.  You may never have to buy bags of dirt from a store again.  Most towns or cities have a landfill.  This is where all of our garbage goes when that big loud truck comes at the crack of dawn once a week.  God bless them.  So look in your phone book and find the number for your local landfill because they also take all the leaves and tree limbs and weeds and landscape garbage there too. 
Your local landfill probably puts all of that landscape garbage into making and selling compost.  I found out last week that our local landfill will fill an entire truck bed of mulch or compost for $5.  I had just bought two bags of dirt for over $10.  Needless to say I took the bags of dirt back and filled up the truck bed for $5.  When we brought the compost home it was smoking (still breaking down) but it was very black and ready to mix in with just a little help.  So I bought a bag of pelletized lime to help cut the acidity of the compost.  It only cost me about $4 at Lowe's.  You don't want to use too much of it if you are planting anything that loves acidic soil (like tomatoes or strawberries) but you will need some to bring the ph to a normal place.  A friend of mine has farm land and he filled his truck bed with a load of dirt from his fields.  Yes, I was blessed with this, however if you have no farmer friend, you can use more compost and till the compost and lime into the dirt on your own land.  This will enrich what you have and still add some fill to your garden bed.  At the very least, if you purchase dirt, I would contact a local landscaper or contractor and have a truck bed of dirt brought in for, no doubt, much less than those bags of dirt at the local store. You can doctor up that dirt with your compost and lime. The raised garden bed will help retain the quality of your new dirt mixture.  I filled in my beds (half full) with compost, tossed a thin layer of lime over the compost and then filled in the garden bed the rest of the way with the dirt.  We then took a tiller and tilled it all together.  The garden beds are full and I only spent $5 on 2 truck beds full of dirt.  You may spend a little more without a farm dirt donation but not nearly as much if you tried to fill it in with store bought bags of dirt.  Make some local calls until you find that compost and dirt cheap.  Happy Gardening!!