With any wedding and any budget for that matter, you can find simple ways to add tons of fabulous detail to your wedding. For me (the very savoy shopper) I try to find things at places you may not normally think of. I personally love Pier One, Ocean State Job Lot, Home Depot, Target, Marshalls, TJ Max, yard sales, flea markets and even on Ebay.
You can save money by choosing one color tone, limiting yourself to two types of flowers and use lots of candles. Buying in volume of one type of flower and one color palette can generally give you a price break. My favorites would be dendrobium orchids and tons of roses. (probably white orchids and 'Faith' color roses with a touch of 'Miranda' garden roses.. mostly white flowers with a simple splash of color will transform any space) Find a great price on pillar candles at Christmas Tree Shops or Ikea. Just keep in mind, most reception venues require everything be contained in some sort of glass vessel for fire hazard reasons.
Buy off season and save a bundle! I find the best deals shopping off season. At the end of summer, you can find amazing prices on glassware, lanterns/luminaries and decor items. As long as you plan ahead of time (come up with some ideas of how you would like to decorate) and you have some extra space to store the items (possibly a garage). Another great find... Goodwill stores. You can find glassware and many vintage finds at wonderful prices. My uncle loves tag sales and usually scours the newspapers every weekend for me. He'll look for listings that say vintage glassware, Tiara ware and even estate sales. (use caution with estate sales, sometimes it's not the best prices)
I find really wonderful things to use for detailing on bouquets at Forever 21 stores and some of the accessory stores in the mall. Etsy and Ebay are great as well. Look for vintage rhinestone buttons, shoe clips and broaches. I have even found wonderful pins or broaches in consignment shops. Keep your options open and keep your eyes peeled for fabulous finds!