Here is a quick run down. JK's can come stock with 32" tires. They can fit 33's with proper backspacing. The most common size for this is 285/70-17 on a 17 X 9 wheel with 4.5" backspacing or stock wheels with spacers that get the total backspacing down to 4.5".
You already bought blingy 18 X 9 wheels. Here are the sizes and diameters for Goodyear Duratracs made for 18" wheels.
275/65-18 = 32.1"
275/70-18 = 33.2"
295/65-18 = 33.1"
325/65-18 = 34.6"
With these choices with that wheel size, I would go with 275/70-18 to give more sidewall. This would not require a lift, and a leveling kit would do nicely with this. The 295/65-18 is about the same diameter, but is wider. Both these sizes give 7.5" of sidewall.
If you go with 325/65-18, you are going to need 2.5" to 3" of lift. These are going to be about 12.8" wide.
FWIW, you can usually find Rubicon takeoffs, all five in new condition, tires and wheels for $600 or less. No lift, no spacers, or anything required.
I am a fan of Goodyear Duratrac. I used to have BFG AT and am much happier with them. I am running 315/70-17. A 17" wheel gives you more options and the tires aren't quite as expensive. I also prefer the looks, but that's just me. I am not fan of rubber band tires or small sidewalls on four wheel drives.
2014 JKU Copperhead Pearl
Too many mods to list. Too awesome to sell.