My requirements:
Input - 220V AC
Output - +-12V
Output amp - more than .5A
Not too expensive (less than $30) and it has to be small. Smaller than 2'x2'x1'.
Has to be hidden so cannot use an external adapter.
Any recommendations? Right now I have the Recom RAC15 12VDA which is too big and expensive.
Thanks.

 

Take a look at firewire adaptors, for instance old iPod chargers. They might fit. Standard FW power is 12v.

 

Do you know how they make the really small ac/dc converters without the coil based system. and why are they so expensive?

 

The transformer-less chargers are SMPS (switch-mode power supply). They're more complex than a transformer, and mostly expensive because of that and because they're newer. The old-fashioned transformer types are soon to become obsolete, I believe, due to laws requiring the higher SMPS efficiency.