I just picked up a 20D that was converted to IR by LifePixel
. I'm nothing but a beginner in IR, but I will say it's more fun, and more frustrating then anything else I've done. The frustrating part (for me) is the post processing, as for now it's all trial and error.
If you have an interest in IR, having a converted camera is worlds easier then trying to use filters. You can use the camera like normal, whereas with a filter, there are many steps involved, and long exposures, and tons of processing. One thing you may consider is picking up an R72 filter, and playing with that for a little while, then see if you want to commit to IR with a body conversion.
Along with the link above, check out LifePixels webiste. Lots of FAQ's and samples. They're also really helpful over the phone if you have any wuestions not answered on the website.