Some people have asked me how I do the perspective changes / perspective corrections when editing images, examples here, also here and many more. I have once written a small how-to which basically tells all: How to eliminate frequent perspective distortions in images. After some hours of practicing, e.g., with the freeware tool I use and recommend, you can do the same.
Below are some of my favourite self-shot images. More images, and more information about myself, is on my User Page in the German language Wikipedia (with quick-translation function to English, French, Spanish and Arabic).