If you insist on American, Knob Creek is one of my favorite Bourbons. It is by the Jim Beam company, excellent.
However, I would highly recommend Jameson Irish Whiskey. If you have never had it on the rocks or neat before, try it. Easily the tastiest and most drinkable whiskey of any type in it's price range, IMHO.
It is in the $20-30 range. To get a whiskey I enjoy more than Jameson, I have had to go into the $40-50 range, and even then I still prefer Jameson most of the time.
And you can make a very Irish weekend out of a bottle of Jameson (and a 12 pack of Guinness and a bottle of Baileys)! Have a couple friends over for dinner Friday night. Everyone can enjoy a nice glass or two of whiskey while you cook dinner (corned beef, cabbage and boiled potatoes would be just fine). Then everyone has a Guinness or two with dinner, and some Baileys for sipping afterward.
Make sure you invite them back for Saturday night, because that's when you use the rest of the Jameson, Baileys, and Guinness for Irish Car Bombs!
(In case anyone is not familiar with the concept: Drop an ounce of Baileys and an once of Jameson into a glass containing half a bottle of Guinness and make sure you chug it, because it will curdle
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