Here is one of my favorite sites. I study it often for inspiration concerning composition with the square format. This artist paints mostly within a square format. His art has given me many tips about composing with my WLF in the Hasselblad.
http://www.fritzart.com/gallery.php?which=harley_davidson_originals
http://www.fritzart.com/gallery.php?which=harley_davidson_originals