This is quick method of creating a fake HDR, will work in just about all versions of Photoshop and Photoshop Elements. Involves duplicating layer, B&W, Invert, Overlay Blend, and Gaussian Blur. Surprisingly, this picture turned out as one of my favorites.
result using Photoshop Tutorial: Fake HDR Effect by Octotuts
This is a web tutorial that uses lots of Shadows and Highlights tweaks. Then uses High Pass, Desat and overlay blend to finalize.
result using Photoshop CS5 tutorial HDR Effect by Justthisgood
This tutorial works in CS5 and above. I followed the author's instructions . This method involves using HDR Toning, I chose the Photorealistc options in presets. The author does a good job of explaining why he is tweaking each setting. When done I made adjustment layers for vibrance (set to 87) and Levels (set to 0,.84, and 255)
result using Photoshop HDR using single photos by IceFlowStudios
Started with a jpg image and opened up in CS5 Bridge as camera raw. Made an underexposed and an overexposed image. Saved them into photoshop, then followed the author's instructions. The result is nice but I'm sure it would be better if I had used camera raw photos.
result from Photoshop Tutorial: Creating an HDR image from a single raw file [In-Depth] by TutorVidCom

Photoshop Magic Episode 14 faking HDR

(2nd Method) - DigitalHeavensuk
This method uses Lab Color Mode. Image is changed to a smart object to work non-destructively.Then Shadows and Highlights is tweaked a bit. Then a curve adjustment layer is massaged followed by High Pass filter adjusted to Linear Light. I ended up not using the High Pass as the result looked better without it. Thankfully I could turn it on and off since we were working non-destructively.
result using Photoshop Magic Episode 14 faking HDR (2nd method) by DigitalHeavensuk

How to Photoshop a photo to HDR photo

There are many diffierent methods to acheive a HDR effect from a single photo.
Here are some excellent tutorals that demonstrate the methods. Below the tutorial link and description is the example picture that I processed using the methods in that tutorial.
sample photo to be used with 5 different tutorials for comparison