Flash AS3 + JSON API

Ok looking for pointers for the resources:

Have a Ruby-on-Rails program talking to Facebook to get the URL of an image. We store that URL using a JSON API into our DB.

We make that data available to a SWF. AS3 is required to communicate through the JSON api to actually load the image.

What we're doign with it: take image of a person's face in it and cut out the face. Save the face for use in a number of different ways (avatar in a game, compiled into a greeting card, dressing it up with wigs, etc.,...)

Questions:
1. Are there pre-canned scripts I can find somewhere to have AS3 communicate with a JSON api to understand URLs?
2. I'm sure you've seen something like what we're trying to achieve (like on JibJab). Is there anything out there (e.g., on StockFuel, free-flash-scripts.com,...) that allows us to ingest an image, identify a vector area and then save an image (as a PNG or a SWF) with everything outside the vector area being transparent? Many games use this for creating an avatar with your face.
3. Is there any pre-canned AS3 script to save resources (this image or SWF) to Amazon Web Services?

I'm looking for:

1. Places to look
2. scripts
3. compiled and editable FLA/SWFs
4. ideas on how to code this
5. other forums / threads that have discussed this

TIA