this is sweet! love the light here...and the shadow. the rigid geometry of the building along with the amorphous blob of shadow works so well.
along with JH, i'm so glad you've found some inspiration in my work! you should check out Hansi Linderoth's stuff too on this site. this shot really reminds me of something he'd shoot.
as for your question on the lens. are you talking about the barrel distortion? or about the horizon being tilted? i've had issues with both. a great tip I got from Thilo Bayer is a PS plugin called PT Lens, which is free on the web (don't know the site offhand). this great program will solve a lot of headaches with your distortion. i'll send you the link if i get a minute today.