The forum search function has been emasculated by the simplification of the forum design but you shoudl be able to put in the camera model and see what pops up. But your best bet is to talk to Canon DSLR shooters. There are more of them who use FCP than FCP users shooting with Canons who hang out here. I should think your best bet would be Canon's software download site.
On the Canon download site go to the operating system drop down and choose Mac OS X., dont choose 10.6 or 10.5. Then choose the EOS MOVIE Plugin-E1 for Final Cut Pro Ver1.2.
Thre is no dedicated FCP plugin for a specific model of camera it is generis EOS software.
I went and got the EOS plug in, but it dodn't seem to help. THat is what I had used in the past to work with Canon 5D and 7D video.
For some reason it didn't work.
I looked in Library > Pro Apps > MIO > Plugins > CanonE1.Radplug>Resources > cameras.plist and saw this information:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<string>Canon EOS 60D</string>
<string>Canon EOS-1D Mark IV</string>
<string>Canon EOS 5D Mark II</string>
<string>Canon EOS 7D</string>
I then added this information:
<string>Canon EOS 600D</string>
I restarted FCP and then was able to transcode the video. I guess that in the US this camera is called the T3i, so it may need to have other infomation inserted. In Southeast Asia it is called the 600D.
I'm not sure if this is relevant for other people, but wanted to post it as it seemed to provide a solution for me. I'm not sure why the download for the Canon 5D and 7D didn't work, go figure. Could just be something strange that I did to my Mac.