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This is a large female wolf spider (family Lycosidae), and you'd have to move a very long way (say, Antarctica) to avoid them, as they have essentially a world-wide distribution. They are voracious predators on any other small arthropods that they can capture, and thus quite useful pest controllers. Although a specimen this large could give you a painful bite if you handled it carelessly, they otherwise are harmless to humans.
That certainly appears to be an egg sac - female wolf spiders carry their egg sac attached to the tip of their abdomen, whereas their close relatives, fishing/dock spiders in the family Pisauridae, carry theirs up front with their chelicerae.