Family PLANNING A WEDDING? BRIDAL SHOWS HELP YOU SAVE: Tying the knot does not come cheap. A wedding in the United States will cost an average of $26,800 this year, according to estimates from the Wedding Report, a market-research organization. And with a dizzying array of choices to make -- photographers, venues, caterers, florists, DJs -- planning a wedding can clobber both your sanity and your