like marlonjohn says hrdshop is the place to be.
for a real quick rundown to do your own you need a camera that can do manual settings.
1) take a range of photos of a silver sphere consisting of the same scene using different exposures (dark to light). Best options to get a silver sphere are at garden centres. The bigger the better up to a certain size for practicability. I've got a 10" sphere and it does the job well.
2) clean them up in photoshop
3) import them into hdrshop
4) touch up the result in photoshop if required
5) export it out as a hdr image
6) import into maya and generate some cool hdr lit imagery/animations
I've got a couple of self generated hdr images a little further down on this page if you want to play with the setup in maya: