If you're attempting to go pro, then only buy the best glass that you can afford.
I use all "L" lens and you should aim for the same.
For the wedding, you will need something wide - 16-35/2.8 L or the newer version (if there is a newer -- this is off the top of my head). You'll need to probably have a good mid-zoom like the 24-70/2.8L.
You can pick up good used lenses at
http://fredmiranda.com in their buy/sell forum. I've sold and bought a few there myself.
Also check out
http://keh.com out of Atlanta. Sometimes they have used lens for sale. Even their "bargain" quality used lenses are great quality - as reported by several pro photogs I know.
We NEED to chat! I can help you find everything you need to get yourself set up. I've been there and done that!!!
Lsia