Check out your local big box stores or nurseries. They usually have a bucket drop off for recycling. Or, what I did my first year I did this, was talk to a landscaping company & raided their garbage dumpster. Got like 50 buckets. Took forever to chop off the bottom. I recommend using a sawz-all to chop off the bottom (PLEASE BE VERY VERY VERY CAREFUL!!! YOU CAN CHOP OFF MORE THAN JUST THE BOTTOM OF THE BUCKET IF YOU'RE NOT CAREFUL!!!). I used a small knife & took about 3 hours to chop 10 buckets. DH then got out the jigsaw & chopped up the next 10 in like 30 minutes.
