If you go to someplace like Radio Shack, you can find an transformer adapter that takes wall current and outputs 12VDC with the appropriate socket for any type of "car"-powered accessory.
That said, I had nearly a year of semi-satisfactory use from my Transpod. It worked okay and put out a decent signal but the volume level was way low - my Monster iCar Play's signal is just as strong and MUCH louder. Also, after about 10 months, mine started going flaky and cutting out randomly. I took apart the power adaptor to look for something that could be soldered if necessary, but all the internals looked fine. I trashed it and I'm much happier with what I'm using now.