Don't know an end-to-end solution, but getting bluetooth on you computer is easy enough. There are enough USB transmitters for less thatn $20.

You can get a FM transmitter kit from Ramsey Electronics and broadcast all over your house. The cheaper models tend to drift a little so you have to retune the receiver, but the sound is first class.

I have had "Net Play Radio" for 7 or 8 years now. You connect it to the speaker or headphone jacks on your computer, You can set it to broadcast (in stereo) on any FM frequency (88-108 mhz) It broadcast anywhere in the house, yard , garage or driveway.
In fact I tune in the radio in my cars to 106.9fm, and listen to the great music I have on the computer whilst I polishing and waxin on the cars.
I also have a radio shack reciever out on the patio with outdoor speakers , and likewise I just choose station "KGLJ" 106.9 fm to hear good sounds out on the patio! KGLJ is Me Gary Lee Johnson
Course if ya live in the East that would be "WGLJ" (LOL)
Anyway it works great and has for a long time now.
We also have a Bose Radio in the bedroom and I likewise tune it in, when I wanna have good sounds and no commercials.
Gary