There are numerous options, such as:
Flash Pro
If your game has already been created in Flash Pro, you could simply target AIR for Android from Flash Pro's publish settings:
ADT Command Line Packager
Likewise, you could simply use the ADT command line packager to build your SWF to an Android distributable.
Flash Builder
Otherwise from Flash Builder, you can create a new ActionScript mobile project:
Select Android, or other target platforms:
Place code and packages relative to the src/ folder, same as you would relative to your FLA:
Your entire Flash app could be published as a SWC, then instantiated from Flash Builder, or individual assets may be exported as SWCs:
Likewise you can programmatically embed SWF assets in ActionScript classes using the embed metadata tag:
[Embed(source="asset.swf", symbol="symbol")]
private var SymbolClass:Class;
var symbol:MovieClip = new SymbolClass();