One of the nicest weddings I went to was a simple ceremony in the couple's home with a small reception after. The bride and groom and some friends prepared a buffet style meal, with other guests bringing dishes - kinda' upscale potluck. We all wandered around and talked and laughed, a friend took the photos, and we all pitched in and cleaned up before we went home.
Have a friend who is handy with a camera take your photos, have friends each bring a flower to make your bouquet, go to the local party store for festive paper ware - and tada! you have a wedding.
You could do casual take away food - like Chinese - or ask some friends who are good cooks to cater it for you. A couple bottles of inexpensive bubble stuff for a toast - or sparkly cider, some nice music on the stereo, everyone dressed up and sparkly themselves and you have a lovely, inexpensive wedding with all the people that are most important.
Don't forget to have your girls play a key role in the event. . They can be your hostesses for the evening. Do get a guest book that they can have anyone sign. Let them be your bridesmaids.
Congratulations on your wedding !!!!!!