About 9 out of ten engines that have set for a long and have no spark the points will be the culprit. Before sanding, filing, or replacing pull the coil wire from the distributor cap and place the end 1/4" or so from a good ground. Now use a screwdriver to open and close the points but don't try to be precise about it--just rattle them around. Even if the contacts are corroded the screwdriver will act as a breaker and you'll get spark. If you do the points need cleaning or replacing and it you don't then it is another problem.
Bingo! That's where and how I start. Fresh battery, make sure you have a good ground at the engine and make sure the points are working. Oh yeah, make sure the key is on
Glad to hear I am not the only one that uses a screwdriver to test the old points.
