Cut your loses and elope! :) That's what I feel like doing some days.
But really...how did the reception place up the price on you? If you don't have a contract, I would do that right now! Don't move forward with them until a contact is signed locking in the price at a certain rate. If you're not already in a contract, tell them you will go elsewhere if they don't come back down to the price they originally quoted you.
Then onto the other things. Have a family member take the pictures for you with a digital camra, or like others have said, find an up and coming photogrpaher who may do it for free or cheap if you give them the right to use your photos in their portfolio.
Have a friend or family member DJ for you off a computer or IPOD. We did this at my aunts wedding and it worked just fine.
For the cake, you can get a small one to do the "cake cutting" if you want, then just get some cupcakes to pass to each person. You could either have someone make them, or buy them at the grocery store, but either way that is much cheaper than a wedding cake.
Make your own invitations. My mom made mine, but with the paper she ended up buying, it still cost like 600 bucks! Wish I would have just done this: Go to Target and buy the pre-made invites. I was just there today and I think it's like 50 invites and RSVP cards for about 24.99!! All you need to know is how to set up your printer for the size of paper and the ink, then you make up your wording and print them out at home! This would be SO MUCH CHEAPER than getting them made or making them yourself with paper you buy elsewhere. (I love my invites, they are beautiful, but it ended up being about six dollars per invite! That is outrageous!!! Most will just throw them out after the wedding anyway).
Don't do "favors" or if you do, do something cheap. I donated $100 to St. Judes Research hospital and they sent me bookmarks to give to each of my guests. They will send you however many bookmarks (or scrolls) as you need no matter how much you donate! If you give $50 and get 100, you are only paying 50 cents per favor! Nice! :) Plus it's helping support a good cause!
Can you change the food options to a cheaper one? If you're having an open bar, change it to cash bar.
Do the flowers yourself. My sisters got their flowers at a weekend market and we put them together ourselves. Don't use flowers for your center peices, as it will be more expensive. Just to something really simple. Use candle holders you and your family have, even if they are all different, or put pictures of you and your fiance on each table. Don't have center peices at all if need be! People eat and then dance, they don't do THAT much or make that much of a differnence! :)
Those are just some ideas on things you can do or change to try to save some money. I completely hear you on the stress though. Everything seems to add up way too quickly. If I knew two years ago, when I got engaged, what I know now about planning I wedding. I would have been married last summer in Hawaii and I would have used the money my parents are helping us with to pay for my siblings and parents to come with us. If there was any left over, it would be a nest age for a downpayment on a house. Seems crazy to spent so much money on one day, but hopefully when the day gets here, the stress will go away and it will be magical! :)
Good luck with everything! At the end of the day, just remember that it's only money, and while it does not grow on trees, it's not the end of the world to be in a little bit of debt :) (That's what I tell myself to make me feel better)