There are a few different processes you could try.
1. If your camera supports +0- exposure, that's probably the easiest. On a tripod to minimize variations due to movement, +-1.0 either direction should give you some good variances.
2. Shooting RAW and using something like HDRPhoto (www.hdrsoft.com) software can mimic HDR pretty well. It's good for processing 3+ offset exposures/white balance shots also. But, will work for a single shot, too. Check it out.
3. Offsetting your white balance +0- in an HDR shot works pretty good, too. But, not widely accepted as true HDR. Kinda like these...