Official Info on Mew

Official Info

This is what Nintendo has to say regarding Mew (through Pokemon.com):

Q) How do I capture Mew?

A) Mew is the 151st Pokémon. However, he cannot be found or caught in the U.S. version. The only way we know of to get him is to win the contest in Pokémon Power Issue 6 in Volume 116 (January 1999) of Nintendo Power (it's too late to enter). It's possible there will be other similar contests in the future.

Some players try to access Mew using unlicensed devices like the Game Shark. These accessories are not licensed or approved, we don't recommend using them and we don't support them. The Mew players get using such a product is not the same as the one they get from the real data--it won't have the same power or capabilities, and the game may experience problems that only erasing the saved data would solve.

You can recognize licensed products by the Official Nintendo Seal of Quality on their packaging.