I second Home Depot. I called them and they said they didn't know what I was talking about. I decided to just go down there and check for myself. The people on the phones didn't know what I was talking about. I went into Home Depot and found it towards the back of the store. I just built my guinea pig a C&C Cage and am planning to build our bunny one this weekend. We are getting him next week.
Awe, so sorry you are having such a hard time finding it. The only bad thing about buying it from Home Depot was that they didn't have the dimensions I needed so I had to buy 3 and tape some parts together. I had a hard time finding the cubes. Our Target/Walmart didn't have them, but I found them at Bed Bath and Beyond. Good luck getting all your supplies and have fun building your cage!
I used to work at Home Depot part time evenings after I had my daughter for extra money. If you are calling, you are the lowest priority. Being in charge of wearing the phone there is like being given the plague. It usually gets given to whomever is the newest or best at ignoring it in the department. Very few are there to provide excellent customer service and really care. They do exist though. It's like the snow leopard. Very elusive.
The real motto there is "You Can Do It, and We Will Watch". They provide 15 minute speed training on a computer in the back. Literally 3 months of information gets thrown at you in less than fifteen minutes and you can't write it down. You then take a test at the end where you can go back and look up the answer. You then pass and become an expert in that department. Whoopie!
Always go down there yourself and find it. Unless you have a local mom and pop hardware store. Now that is service. Our local True Value Hardware is da bomb!
So I finally found some! I went to a large scale art supply store in Alanta. It cost be $21 for a 4x8 or 4x10. Glad to finally have found it! I went to several Home Depors and the employees helped me search all over, but no luck. Looks like I'll be making a cage tonight!
Don't buy it, go to a sign shop and tell them what it's for and ask if you can have a sheet or some scraps(or maybe a sign that went wrong! bunnies can't read!). You may have to tape some together, but free is free and free is awesome. ;D Plus the sign shops don't really mind since you won't be making signs so your not competition. Usually the managers/workers get really interested and they're amazed at what you're doing.
I've done it twice. First time I got a 4x6 sheet, second time I got two 2x1 sheets but they offered me more. I'll probably never buy coroplast ever.