That will allow me to use all my 52mm AE1 lenses on The EOS system, 20 d rebel etc....and where may I find it.

I've seen aftermarket (as in not made by Canon) adapters show up on ebay from time to time. Not being a Canon shooter myself, I'll have to let someone give more specifics. I'd wonder if you'd get any meter coupling, automatic aperture, etc.

PS: I think the 52mm is the filter diameter (on the front of the lens) which doesn't have anything to do with the lens mount. I believe it's FD mount that you're looking for - but again hopefully someone else can verify this.

your right i didnt mean to put the filter size in there like that my bad

I have never seen anything like this, but then again, that could be because I have never looked for it. :) It would be nice to know tho, since I too have an AE-1 with several lenses along with my EOS gear.

You are right Steve, it's the FD mount that the AE-1 uses, along with the FL mount.

There are, if you can get a canon adapter(good luck), you will end up spending probably 300-500 dollars for one. The reason being that to use the adapter and keep infinity focus, you need glass in the adapter. Canon made a few back in the day, but there aren't many left, and I have seen a couple on ebay, but for alot more than they are worth. Better off saving that money for new lenses. I made an adapter(no glass) for strictly macro work, essentially an extension tube, and it works well, but it's fiddly working the aperature lever. So anywho, there are off brands, but they suck!

You are CORRECT! The cheaper one is a " Macro Lens Mount Converter FD-EOS " which loses infinity since it is essentually an extension tube. They cost around $200 or so if I remember correctly. The non macro one(Canon lens coverter FD-EOS ) was VERY expensive compared to the macro one! These were made for PRO type lenses to be used on the NEW EOS mount cameras way back in the early 90's I do believe and became pointless to still be manufactured after a short while . That one is essentually a TC ;)

http://www.farah.cl/CanonFD/#fd-eos

http://www.adorama.com/CZFDEOSA.html

http://www.bobatkins.com/photography/eosfaq/manual_focus_EOS.html

http://photonotes.org/articles/eos-manual-lenses/

http://www.rit.edu/~andpph/text-eos-to-fd-adapter.html