Following on from Abernovo's suggestion, there are the Shardlake murder-mysteries by CJ Sansom, the main character of which is a lawyer in Henrician England, and each book deals with an aspect of his legal practice. As novels they're bloated and info-dumped, and Shardlake is too frequently a modern liberal in his outlook, but the legal aspects are well done (Sansom himself is/was a lawyer, I think).
Anyhow, your world-building sounds very intriguing and I'm kicking myself I've never thought of something similar, since as sknox says, this duplication and overlapping of jurisdictions and the bewildering labyrinth it could produce is very typical of how it was in reality -- indeed, how in England it continued to be until the C19th in some respects.
However, I'm not sure that just bolting on English Tudor or Elizabethan law to your world is exactly the way forward.
Very crudely, law comes from culture; culture arises from history; history is born in geography, and all (well, all save geography) are housed within a shifting framework of pragmatism and idealism, economic reality and the Four Horsemen. Change one element and the rest change to a greater or lesser degree. For instance:
- under Henry VIII men had to practice so many hours at the weekend with the longbow. There's no standing army, and Henry believes in war as a means of accumulating wealth and prestige, so he needs men ready to fight, and even if he were less warlike, the continental powers aren't, so soldiers would still be needed. A pacifist monarch in a time of peace, or living on a island far enough away from warring countries isn't going to need a law of that kind.
- I thought there was a law in Elizabeth's reign requiring all bodies to be buried in shrouds made of English wool (though looking quickly the only statute I've found is from the 1660s) -- it's an economic decision to help out sheep farmers when the price of wool has plummeted. Under different economic conditions, no such law was needed in previous centuries.
- Elizabeth enacted laws requiring attendance at church with fines for non-attendance. At a time when she's under real threat from Catholic nations abroad and her advisors fear traitors at home, they use the law to try to force Catholics into the open. Again, not a law that's needed when there is no such internal threat, real or perceived.
- under medieval and Tudor law, a married woman was a feme covert, with no legal personality of her own -- unable to contract her own debts or run her own business (though local custom might allow for this). This is a direct result of inequality between the sexes -- in a more equal society there would be no law of this kind.
- sumptuary laws forbade certain articles of clothing or fabrics being worn by the lower classes. Again, a more equal society would have no such laws.
So while looking at Tudor laws would be enormously interesting, you need to ensure that your invented nations/cities have the background which would provide for similar laws.
By the way, while statute law isn't the be-all and end-all of the legal system, especially in a common-law jurisdiction, it does show you what the government of the time is worried about. Wikipedia has a list of some of the more important Acts of Parliament passed in the Tudor period which it might be worth glancing at
Category:Acts of the Parliament of England (1485–1603) - Wikipedia