You have two options. One is the "synch" route, where you record video with the recorder and sound with normal recording processes, then manually synch the files together.
The easier/better way is to use a prosumer camcorder that accepts an external mic jack. XLRs are idea, but most will be standard 3.5mm stereo jacks. I have the latter on a Canon VIXIA HF100, and it was the main reason I selected that particular camcorder.
Here's the signal path I use:
1. Mics (either a stereo mic /dual XLRs on the end, or two condenser mics using a "Blumlein Pair" configuration for surround sound recording. Google "Blumlein Pair" and you'll learn more.
2. The mic cables plug into a JuicedLink JL-CX431, which mounts on top of the tripod. The camcorder mounts on top of that. The JuicedLink is a combination preamp/mixer with four channels of XLR inputs. Works fantastic - highly recommended. See
www.juicedlink.com for info. That site, BTW, has a slew of great videos that teach you how to record excellent sound with a camcorder.
3. A short cable runs from the JuicedLink into the camcorder's 3.5mm stereo jack. Everything is recorded direct to a SD card in the camcorder.
Sound is manipulated with your video editing software. I use Pinnacle Studio HD. It outputs the sound in a variety of formats. I usually use 16-bit stereo @ 44kHz (CD quality), but you can go higher than that if you want for manipulation in ProTools or whatever. The file is already synched with video so it's no big deal to drop the sound file back with the video track. BTW, Pinnacle has a bunch of sound editing tools built in so there's little need to export to a standalone application. Pinnacle is enough for me, especially for live sound.
This is not rocket science. Follow the steps above and it's easy to get fantastic sound into your camcorder.