A DSLR camera would greatly help, but I only have an old digital camera and iPad at my disposal. The 5 Minute Librarian offers 8 simple photography tips on how to take better photos even if you don't have the budget for a DSLR camera. The productivity blog Lifehacker also has great tips for using a smartphone to take photos.
Don't forget about getting permission to use those fabulous photos. DPI has guidelines: http://dpi.wi.gov/pld/lsta/faq/photos.