I agree with iridflare and lare... before you jump in, we hope you realize that the video capture is a part of the "system". You will likely also want to add to your list:
1) More than one camera. Three is a good start.
2) Tripods and other "steadying" devices. Since capturing handheld is not a good idea, then some sort of shoulder mount or a vest system with articulated, counterbalanced arm - like a Steadycam system. I know a few who use camera cranes. I like Kessler cranes on their Hercules head + K-Pod tripod.
3) Lighting. This will be both ways: camera-mounted LED lights are very useful - and for those poorly lit venues, a couple of light trees and a bunch of PAR56 cans (LEDs are preferred, but incandescent lights still work (they get hot - they are usually for stage lighting) with dimmers or DMX controllers. Perhaps a couple of large LED panels on stands. LitePanels are good. PAR cans, light trees, trusses and lighting controls are available from GuitarCenter and several other places.
3) Power supplies - if you want portability, then high capacity batteries from the camcorder manufacturer or battery belts for the cameras/lights.
4) Cases. Pelican makes great gear to protect the expensive electronics. Anvil makes great wood cases for the lighting and other stuff.
5) Cables for power and audio. And storage boxes cases for transport. Lots of gaffer's tape. DO NOT use duct tape as it can leave a gummy residue that will cost you LOTS of money to pay out for cleaning/repair.
6) Mics: There is no single "best" mic. Use a good wireless lavalier for vows - Sennheiser, Audio Technica, Sony (pro), EV and a few others... the systems with a portable base station to mount to a camera or take up small space when connected to a standalone audio recorder. If more than two mics are used, then a small mixer will be needed. A couple of good handheld mics for "toasts" and other speeches. These can be wired or wireless. You can get wireless modules that turn the (formerly) wired mic into a wireless mic. My Sennheiser G2 and G3 systems have them. A couple of of shotgun mics with fuzzies or blimps for windy outdoor ceremonies...
7) A separate audio recorder. Depending on the requirement, this can be as simple as a Zoom H2n or H4n or a Fostex field recorder... or as complex as a ProTools rig front-ending a computer for multi-track audio. A 4-8 channel Mackie mixer is handy to have around.
8) Other accessories: Headphones for monitoring the audio during capture (one per camera - you don't want to shake the camera plugging-in/unplugging); on-camera monitors; if multiple people are staffing the cameras, then a wireless intercom communications system so everyone can communicate is *really* useful. Good cameras have a wired LANC port - use of LANC units are strongly recommended - these can control power, zoom, focus... so the camera does not shake when these adjustments are made. The LANC attaches to a tripod handle or can be handheld.
There's more, but this is a good starting point... And we haven't gotten to the computer(s), editing applications, DVD authoring applications, printer capable of printing on to the DVD (no stickers), archiving the video...
And don't even think about using a dSLR - unless you have several. Anything under about $1,800 will overheat after about 20 minutes of continuous video capture (so while one is in use, the others are cooling down). dSLRs are great for still image capture and b-roll video capture.
If you have already thought through the above and this really is about video capture only, suggested devices (remember, more than one):
Entry level: Sony HDR-FX1000, Sony NEX-EA50UH; Blackmagic Design pocket cinema cam
Step up: Sony HVR-Z5; Canon XF300
Step up: Canon EOS Cinema Cam C500; Panasonic AG-AF100; Blackmagic Design cinema cam. There are LOTS of others that are equally good - even better.
I do not understand what a camcorder has to do with "high proficiency" - it is up to the camera operator to be proficient. A"nice looking" camcorder has zero to do with video capture/edit video quality.