In pretty much every league I'm in where tiebreakers are necessary after 162 games to determine who goes to the playoffs, owners have questions about how they work. I've compiled here answers to some of the most frequently asked questions.
1.) WIS uses MLB's rules for handling ties. A good summary of the MLB rules can be found here: http://www.baseball-reference.com/bullpen/Resolution_of_ties_in_division_races
2.) When 2 teams tie for the division title, no play-in game is needed if both teams already qualify for the playoffs (in other words, if both teams have better records than all other teams that were in contention for the wild card). See scenario 1 in the above link.
3.) If 3 or more teams are tied for either a division title or a wild card spot, WIS uses a round robin (as described in scenario 5 of the above link). Suppose teams A, B, C all finish with identical records. A and B are tied for the lead in their division, and C is the second place team in another division. A and B will play first to determine the division title. The loser will then play C for the wild card. Note that even though the loser of the first game will now technically no longer have the same record as C, they are still considered tied.
4.) It is not clear to me how WIS resolves ties when play-in games are not needed, nor how they determine home field advantage. They may use the exact tiebreakers used by MLB; they may use a different set of tiebreakers, or they may just use the equivalent of a coin flip. If anyone knows, please post.
(UPDATE: Thanks to pinotfan for posting the correct answer to this, from the Knowledge Base.)