One thing all members should tell new people is to look around in the forums before posting. There are already a couple of topics (I believe) that mention the release date of HG/SS. It will be different depending on where you are, but use some math to figure it out.
I'll link the topic later.
Hope this helps!
Edit: Here's one topic that talks about the games. If it's not there, browse a little more to see if you can find your answer. http://www.psypokes.com/forums/viewtopic.php?f=51&t=24549
It's great to complete a Pokedex! So I'll need some help...
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