Bird Feeder

This feeder fits a Coke bottle.

http://www.thingiverse.com/thing:1673557

Bottle Feeder Hook

You will need something to hang it up.

https://www.thingiverse.com/thing:175640

Bottle funnel filler

Now you have the bottle feeder and a hook.

Now how to fill the bottle with seed.

Try this https://www.thingiverse.com/thing:4876877