to follow what Jacko said, you want at most a 35 aspect ration (sidewall height) on 19's, if not 30's
Here is my car with 19x9 and 19x10 wheels, and 265/30/19 front, 285/30/19 rear - offsets are +23 up front, +24 out back (though I am using a 5mm spacer in the rear right now, so effective offset is a +19).
To further complicate things somewhat, you get the situation where not all tires are created equal. For example, a 285/30/19 tire obviously is for a 19 inch wheel as the name suggests. However, its also "supposed" to be 285mm in section width - such is not always the case. Just like not all "larges" on shirts are the same physical size (varies store to store), or like jeans from one store and jeans from another, despite being the same size, are not cut quite the same, such is the situation with tires. You've got tires that run a bit narrower, and some that run a bit fuller.
My own tires are Bridgestone RE050, which run on the fuller side of things, making them even wider than their "size" suggests
Getting the right overall look is about the relationship of your tire to wheel to car - when these three things play nicely, you get a car that not only looks purposeful, but performs equally well. Push the wheel and tire too far out, and you suffer massive alignment issues that can take time to sort out (ie, offsets down into the low teens with super wide or super skinny tires). You'll find these cars to handle in a very "darty" fashion. It can be all corrected with proper alignement specs but not every shop is capable enough to know these specs, let alone dial them in.