I just went through this last week, here's a link to a GREAT guide put together by Jax184, helped me alot.
But in the meantime, to test for spark, unscrew the plug from the cylinder. put it back into the cable, and place the exposed metal tip against the cylinder (just next to the hole you took it out of) Then put your keys in, swith to run, and kickstart, you should see a spark.
As for the battery question, I asked the same thing, NO you don't need a functioning battery to start, but you should have one in even if it's dead, to avoid burning out your headlight.
If you find out how to charge it, let me know!
Guide to Express repair (LONG) - by Jax184