There's definitely a lot of cheap Meers to be found on Ebay if you want something inexpensive to start out on. I'd recommend buying new, as I wouldn't trust a used one from just anyone (if you look at the pics of a lot of used ones on Ebay, the rim of the bowl is charred to shit and probably caked with carbon inside as well, both NOT good at all).
Another nice thing about Meers is that you can smoke 'em multiple times a day, unlike briars which need a lot of rest, just make sure you don't let carbon cake build up inside the bowl.