Calm down, that shit be makin you paranoid yo!
Seriously, there is about a 99.99% chance that there was nothing going on other than a phone tech chilling in his van. I work for a large telephone company, and its a very common practice for a technician to just chill in their van while they do any of a number of things. He could be filling out the records reports for the work he just performed; there are massive databases, and customer drawings, and physical plant maps that all have to be updated any time there is even a minor change in the network. Another possibility is that he did not have another job to go to yet. The van is their office, and if they don't have a pressing task to complete they will hang out and check email while they wait for the dispatching office to give them a new task. It wastes gas to drive back to the home office unless it is needed, so we encourage our guys to stay put sometimes if we think there might be something else coming down the pipe later that day in the area. A third option could be that he was taking lunch. As I previously mentioned, the van is their office. It is very common for our guys to pull across the street into a shady spot after a job to eat their lunch and listen to the radio or read a book for their lunch hour.
Nothing harmed by his presence I hope? In the future, if you truly are concerned about the activities of a phone truck, write down the van # that will be printed obviously on the back of almost all telco vans, and call the 1.800.# that will also be there. The local manager will be on the radio within minutes of your call to check up on him. No harm done.