Replying to Help - Wedding Videography

So a very close friend is having me film their wedding this weekend. What type of equipment is absolutely neccessary for this to be a good wedding video. Can someone send links to cheapest gear but good quality. WIll i need some sort of camera light in the dark hall while dancing at the reception. (using t3i). I need links to some good wireless microphones. Maybe a link to a good monopod and cheapest t3i batteries. Good priced SD cards. Im very under geared here, but im dedicated to make this as good as possible for my friend whom ive known since age 6 :p . Any tips and techniques will be appreciated thanks guys!