I'm going to move you to our For Beginners forum, as your question is really more about getting started developing games than it is about game design.
It's good that you're looking to make a simple game to begin with, but let's get some information so we can help you to get started properly. Obviously you've chosen to use ActionScript3 to make a Flash game; this is a good choice, and one that will allow you to make some money off of your games once you've learned the basics.
1. To begin with, what operating system are you using? If the answer is Windows as I suspect, which version are you working with?
2. Secondly, have you chosen which tools (Adobe Flash, Flex Builder, FlashDevelop, HaXe, etc.) you will use to create your games... which one are you using? Have you got it installed on your computer and ready to use, or do you need help setting up your tools?
3. Next, do you have any experience yet, or are you starting from scratch? If you haven't learned a few basic things such as loading and displaying a graphic on the screen, you'll probably need to go through a few quick tutorials on that before we look at starting on Tic Tac Toe (naughts and crosses for anyone unfamiliar with that name). Note that we're not going to just give you the source code to a tic-tac-toe game, and if we did it wouldn't really help you to learn -- but we can help you out with tutorials, resources, advice and trouble-shooting to help you write your very own!
I'm not going to offer any further advice or links yet, as it may or may not be relevant based on your answers to my questions above -- help us to help you, and let us know your answers to those things so we can offer further information!
i am using windows 7 Ultimate.
i have already installed Adobe Flash 3.0, all components required are ready.
i have few knowledge about this thing like tweening.. changing images to movie clips, buttons or graphics.. i know how to publish it and run it.
but when it comes to source code writing my leanings are not enough, i know some basic codes because i am quite familiar in C++ Syntax.
Sir, if you could send me links that will give instant source code to tictactoe playing multiple users, would be very useful because i know how read codes, but
i do not know how and when to use it during coding.. i chose tictactoe because i used to play this and i know the rules of the game, it would be very useful for me
to interpret and understand the codes... thank you for giving your time answering my post.. Godspeed!