12 inch styrofoam balls

What are you making with them? If you are covering them, papier mache may be the best way to go, but if you have to pin or stick them with things, foam will give you the best hold. Polystyrene might be a good substitute as well. And will be a bit cheaper. Also, 10" vs 12" saves a lot of $$$ too.

http://www.amazon.com/FloraCraft-Packaged-Styrofoam-Snowball-Package/dp/B002PNP4RE/ref=pd_sim_misc_7?ie=UTF8&refRID=1GQWPKXSWW4BVMFXM0HA

I'm trying to use them in replace of a styrofoam ball for my center pieces. I would be sticking them and my concern with the papier mache is the lack of hold. Here's a picture of the first sample center piece i created.

Here's a thought... Idk if wiffle balls would be big enough though...

http://www.pinterest.com/pin/350577152215227274/

Wow! Really pretty! Maybe you can buy smaller and wrap them with something to reach your desired diameter? Try searching craft stores and try getting a deal on "damaged" balls. They will be completely covered in flowers --- so nobody will know there is a chunk missing. Always worth a shot!

I saw some of those green foam flower things at the Dollar General when I was looking for candle holders. Not sure what shapes or sizes, but might be worth a look.

Blow up ROUND balloon, wrap with glue-soaked string in a criss-cross pattern, after string dries, pop the balloon. Light-weight ball with holes to stick flowers into!

Did you try walmart?

Try and see if Hobby Lobby ever puts theirs on sale. I know that they have a certain rotation for things that are on sale.

Http://www.save-on-crafts.com/search.html?keywords=Ball#/keywords=ball&Category1=Floral+Supplies&Category2=Floral+foam

I got mine from save-on-crafts.com - they had the cheapest prices and I looked everywhere. My centerpieces are similar to yours.