Well the Tokyo Mew Mew's each had a tattoo located somewhere on their body. Also I think the sudden transformation would give it away.
Tokyo Mew Mew actually, it's an anime. It has an English adaptation called Mew Mew Power, but unfortunately it was never finished. You can watch Mew Mew Power and Tokyo Mew Mew both of YouTube and where ever else you can find.
On Ebay!
try AbeBooks, eBay or Amazon. You can also find Tokyo Mew Mew A La Mode (season two), if you're interested
Episode 42
Ebay
no
Mia Ikumi wrote Tokyo Mew Mew and Tokyo Mew Mew A La Mode.
Tokyo Mew Mew a la Mode was only a manga as far as I know. So all you can really do about Tokyo Mew Mew a la Mode is read the manga online. The best place for that I think is http://www.mangafox.com/. There is no Tokyo Mew Mew manga on http://www.onemanga.com/ : if there is, I can't find it all.
Episode 44
in the anime no
Tokyo Mew Mew was made in 2002
Tokyo Mew Mew came out in about 2005