ah, the memories
Anyway, here are a few suggestions the ex and I used when we got married:
Wedding Dress: Consider
renting a wedding dress. Yes, there are places you can do this. Unless you really enjoy hauling your dress from apartment to apartment over the decades. If you need a momento, make your own HAT.
Wedding Cake: Why go to an expensive cake decorator when you can usually get a great wedding cake from the bakery at your local Safeway? You can also get the little mints, nuts, whatever. You just have to be willing to coordinate setting it up (delegate to a sister/cousin or whatever if possible).
Decorations: Most people know to make their own table and church decorations.
My current wife and I made our own invitations using the computer and her scrap booking skillz. If you have an aunt or someone into scrap booking, ask if they'll help you.
Music: Not as romantic as hiring a band, but we hooked up our CD changer to the reception hall's speaker system.
Become a member of a church. Yes, church's discount their halls for members. Of course, if you join the day before you book, it might look a touch suspicious.
Anyway, good luck to you!