I finally found this song.
I couldn't find the CD for purchase, but I found an mp3 download of the Motorola version of "Radio in My Head."
You can DOWNLOAD IT HERE for free at minorcrisis.net, a file-hosting service. Look under "Uploads hosted by michlynn1968". Put your pointer over the green arrow beside the song title and right-click. Select "save target as". When the "save as" dialog box pops up, make sure you add .MP3 as an extension before saving and beginning the download. There's limited bandwidth, so please drop me a comment and let me know if your download was successful or unsuccessful. You can also find it on LimeWire.com, using their software.
I'm surprised that it's so hard to find information about Pu Shu in English or find his CD anywhere in America (or on the Internet!). "Radio" is such a great Asian pop/dance song and would be an instant hit in the U.S. if it was played on the radio.
I have to give credit to the Backstreet Dormitory Boys too, for doing a lip synch video to the song, or else I never would have known it existed.

Update (October 26, 2007): I got a request for the lyrics to Radio In My Head. I don't know how accurate these are (the English or Chinese translations). I found this in the forum section of The Chinese Music Blog.
The Lyrics to Radio in My Head
Wo hen qiong, er ni fu you (I'm poor and you're rich)
Ta hen ji mo, yi shi wu cheng (He's lonely, nothing is accomplished)
In beijing street
In usa
Gan dao kuai le hai shi nan shou (Feel happy but still feel bad)
Anytime i feel the radio
Oh, it's my radio
In my head
Ye bu fang rang wo zi you (Also doesn't stop me from being free)
If i listen to the radio
Oh, just my radio
That all my life
I'll play my sounds to you
Wo hen qiong, er ni fu you (if i was a girl on rich new york)
Ta hen ji mo, yi shi wu cheng (i am a boy, or a pretty girl)
In beijing street
In usa
Wu suo wei xi yue hai shi lang bei (Don't care whether it's happy or bad time)
Anytime i feel the radio
Oh, comes my radio
In my head
Ye bu fang yong you zi you (Also doesn't stop me from having freedom)
If i listen to the radio
Oh, just my radio
That all my life
I'll play my sounds to you
Anytime i feel the radio
Oh, comes my radio
In my head
Ye bu fang yong yuan zi you (Also doesn't stop me from having freedom forever)
If i listen to the radio
Oh, just my radio
That all my life
I'll play my sounds to you