I have the same sort of thing as the chinese thing with the USA power adaptor, Bluetooth from phone ( linked to it) and audio output to holes in back of HIFI using supplied lead like the thing I found. Not to sure what you are asking but ebay is your friend with a few words in it's seach box.
Bluetooth wireless speakes exist or do you have some normal wireless things already with a transmitter unit that needs an audio input that could be straight from the phones 3.5mm photophone output. Guess you want the phone by you and souns wireless to some powered speakers so a few ideas.
http://www.ebay.co.uk/itm/New-Bluenext-Bluetooth-Ste...
http://www.ebay.co.uk/itm/Wireless-Home-Audio-Speake...
http://www.ebay.co.uk/itm/BLUETOOTH-WIRELESS-SPEAKER...
http://www.ebay.co.uk/itm/Creative-D80-Wireless-Blue...
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For the thing from china with the funny USA power transformer
http://www.ebay.co.uk/itm/EU-US-AUS-UK-AC-Power-Plug...
Something there or similar is what you want I guess to make use of the bluetooth on the phone. I do to play country music (the good new american stuff, better than our top 40 pop!) from a web site fired up on the phone and logged onto the internet router.
I also have a HTC all singing dancing phone.
Or what suggest above might do but guessing you want a cheap way to get music by bluetooth on the phone. Only works in the same room and 10m range, I dn't think so. With a wall in between, no way. Don't expect to much. Bluetooth very short range. Almost useless sometimes for this I think you want. Works but 4m is about as good as I get in a brick wall flat.