Clean a dirty wedding dress?

I just got a wedding dress from a family friend who wanted to pass it down to me. She wore it when she got married and it is stained. It has been in the closet for years. This is the only dress I want to wear. There is a brown spot under the see through lace. It has also yellowed. It still looks beautiful. wedding dresses,designer wedding dresses,bridesmaid dresses wholesale,The veil also is yellowed but it is long and the dress has a long train and the veil is long with flowers on it that I want to keep. The head dress part, is bent. I plan to replace it. How can I clean it at home? Any suggestions? I am getting married March 8 2008. There is so much to do in so little time.