Site inspection: physical configuration of power lines, poles, vegetation, including primary and secondary conductors and service lines.
Evidence: any removed by the power company?
Repairs: what did the configuration look like before the loss and what does it look like now?
Documents (I've used names that may be different among power companies, but the description should give you the gist of what you're seeking):
T-man (Trouble Man): reports, observations at site. He's generally the first sent to the scene by the power company.
Crew: what did they see, repair, and why. They're sometimes called in by the DO or T-Man to repair the site.
D.O.: Distribution Operator: daily reports. He is responsible for day-to-day operations and is generally who the Fire Department calls in the event of electrically-involved losses. He generally dispatches the T-Man and/or crew.
I.R.: Inspections records of periodic inspections of lines and equipment, recommendations for repairs, repairs actually made.
Governing regulations/statutes/standards: usually a public regulation or law. (In California, it is General Order 95 (GO 95) of the Public Utilities Commission. Also, the power company has its own standards for operations, inspections and repair. (21440)
Obtain as much of the above as you can, but be prepared for a fight with most power companies, perhaps in litigation.