Salon Services may have a store near you, theyre really good, supposed to supply to salons but do sell to the public too. I bought some funky coloured ones from them save adding colour to my long hair for nights out.
I get mine from www.hairextensionsnow.com
They do a range called Clipinz, which are made from real hair, and you can send a sample of your own hair for them to match a colour to it. Mine are an exact match for my hair, and they are so perfect, and really cheap