First thing to do - try a new plug, $4 fix IF it is the problem, if not - at least you have a spare.
Grounding the plug outside the block in a dark situation will tell you if you have "spark" too.
this is a tool to tell if spark is present too:
http://www.amazon.com/Fool-proof-En...939&sr=8-1&keywords=small+engine+spark+tester
I would take and clean the connections once again.
Meter is tough to use in this situation, you are taking a magnetic field and passing it through another one and then a circuit is opening allowing a 20k volt to pass in a millisecond.
But IF the coil is shot - you will get a open circuit reading infinity - if you have a short - it will read damn near zero ohms.......not sure what the resistance of a "new" coil would be.
You can test your switch quickly - do a simple continuity check on it.
Best to see it !
OR you can do it the ol' fashion way.......
Hold a screwdriver under the insulator and touch the metal of the screwdriver as you hit the starter