heres some quick tips from me
1) DO NOT TRY HDR AT A WEDDING!
2) your idea of having some sample ideas handy is very good, do you have an iphone? just stash them in that and you can get easy access to quickly scan them (easier and more on hand than a printed book)
3) everyone recomending the 50 f1.8 II is right it is cheap and good, dont use it wide open too much around f2 to f2.2 its quite nice and sharp but still gives nice shallow DOF
4) try borrow a second body changing lenses is hard when the pressure is on
5) consider renting s 17-55 f2.8 for the day for your main lens this will make a massive difference over the kit lens (if you rented this you could probably get away with not bothering with the 50 f1.8 and thus eliminating lens changes altogether) 1 less thing to worry about
6) dont shoot groups of people with wide apertures a easy rule of thumb is make sure your aperture is about equal to the number of people in the shot with f8 or f11 for really big groups
7) research and learn second curtain sync and dragging the shutter (I posted some detailed info about this in another thread a while ago i cant remember exactly which one) this technique will allow you to use not too high iso slow shutter speed flash and still get sharp shots in low light events. practice it alot before hand get your wife or girlfriend or both to dance around in a low lit room and practice until you are confident of this techinique
It is essential.
EDIT: found the thread http://www.canonrumors.com/forum/index.php?topic=12673.45
learn about balancing flash and ambient exposure this avoids the bunny in headlight look or the flash didnt have enough juice look
9) carry lots of spare batteries for cameras and flash and spare memory cards
10) bounce flash when you can but dont be afraid of using direct flash either
11) wear black clothes you dont want to show up in a bright hawian shirt as a catchlight in the brides eyes
also it will stop you casting any reflected colour cast from spilled flash light
12) make sure you get detail shots of decorations, brides jewelry, shoes table decorations etc you dont need a macro for this just get the shots
13) shoot different angles dont just take every shot from standing eye level otherwise they will all be snap shots so play with some creative angles.
there is plenty more stuff to think about, weddings are full on and high pressure but fun too
goodluck and post back with pics