I can't get that page to load, but I'll share some things I've learned when photo sourcing textures:
1) Take the time to line up your shots at a perfect angle. It takes seconds to adjust the camera alignment, but sometimes hours to tweak a poorly aligned shots in photoshop.
2) Zoom in (if you have optical zoom) to minimize distortion. Use something like a brick wall to find the "sweet spot" on your camera where things aren't distorted. The bricks should line up perfectly along the edge of the view finder or LCD screen. If they are bent or warped at all, it's almost impossible to fix in the editing stage.
3) Get the right lighting, or don't bother. In most cases, some good sun light is required, otherwise the textures will come out looking bland. If there are shadows from trees or other objects, you might as well not bother taking the photograph as those types of things can't be edited out easily. Indoor lighting is also bad, unless you want a gradient of lighting on your texture surfaces. Using the flash indoors can compensate for this so long as the object is fairly close and is not glossy.
