Nice job Phil. I really like the photo of the bridge. It draws your eye back into the depths of the scene.
There are a few ways you can help the camera focus. 1. You can use a focusing card (black and white with concentric designs for your camera to focus on- it will need to be light enough for the camera to recognize. 2. Once your camera and tripod are set, I manually zoom in as far as I can at a mid point or focal point in the lighting scene. I then manually focus through the view finder and then back the zoom off and compose the frame. (I do not put it on automatic focus once set for that location.) If you change the aperature setting (f/stop), you will have to re-focus. I just bought a D7000 that has a dedicated mirror-up function and am also using a cable release cord. If you do not have an option for a cable release, set your timer for 10 seconds and this will help with the clarity of the shots you are taking. Shoot in manual mode and set your ISO to 100. This will make your shots less grainy. I always shoot in digital RAW, this will help you if you need to tweek anything in post using photoshop or other RAW converter plug-in.
Keep up the good work- Looks good Phil.