I drink a lot of whiskey and at this point have more invested in my bourbon collection than in my knives (and I've got quite a few of those as you know). I like cask strength bourbons and I have a lot of favorites in the 120-150 proof range. But you have to work your way up to that, can't just start drinking 147.7 proof bourbon neat on day one. And while the cask strength stuff is great, my preference is for bourbons in the 100-115 range. Properly produced and then aged, they don't require much water to bring them down into this range. The less water you add the better. I also rarely use bourbon or rye in cocktails that is less than 100 proof. With the affordable and delicious Bonded offerings I mentioned above, there is no reason to use more expensive and lower proof options. And quite often it actually makes a worse cocktail than the cheaper, high proof option.
Figuring out who makes each brand can help you in your purchases as well. Companies like Jim Beam and Buffalo Trace produce many many different brands. If you like one, you might like other things they offer. Less risk when buying more expensive options. Also, if you like their high end stuff, definitely try their cheaper offerings as well.
There are also many brands out there that actually don't make anything, they just purchase bourbon or rye from other people and bottle it themselves. I prefer to not buy things from these types because from a value perspective it's usually just cheaper to get it directly from the source (or from someone else who uses the same source but sells it cheaper). Brands like Bulleit, Templeton, Angel's Envy, Noah's Mill, Rowan's Creek, Whistle Pig, etc are all in this category of Non Distilling Producers (NDPs). If you like Bulleit rye, try George Dickel rye. They get it from the same place (MGP of Indiana) and the Dickel is usually cheaper. And remember, the brands you recognize from advertisements are going to cost more because they spent all that money on the ads!
The other thing I tend to avoid is craft distilleries. Unlike knives or anything artisan, bourbon is better made on a large scale. Companies like Buffalo Trace have been doing this a long time and have experimented with many different mashbills, barrels, entry proof, aging conditions, etc to test what makes the best bourbon. The other thing they have on their side is time. It takes time to properly age bourbon. It just starts to get good at 4 years old, but really benefits from being 6-12 years old. Craft distillers don't have the resources to wait 6 or 10 years to put products on the shelves. So instead they often put very young whiskey out. And while some of it is decent or interesting, it is often not good bourbon, especially compared to what the big guys can make and put on a shelf for $20-35.
Here are a few fairly common options that I feel are a good value. Getting at least one from each distillery will help you identify which house flavor profiles you prefer.
Old Weller Antique (Buffalo Trace)
Weller 12 year old (Buffalo Trace)
Old Grand Dad Bonded (Jim Beam)
Old Grand Dad 114 proof (Jim Beam)
Knob Creek Single Barrel 120 proof (Jim Beam)
Booker's (Jim Beam)
Fighting Cock (Heaven Hill)
Henry McKenna Bonded (Heaven Hill)
Elijah Craig 12y0 (Heaven Hill)
Elijah Craig Barrel Proof (Heaven Hill)
Four Roses Small Batch (Four Roses)
Four Roses Single Barrel (Four Roses)
Four Roses Single Barrel Cask Strength (Four Roses)
Smooth Ambler Old Scout 10yo (MGP)
Abraham Bowman Single Barrel (Buffalo Trace)
Old Forester Signature (Brown-Forman)
Wild Turkey Rare Breed (Wild Turkey)
Russel's Reserve Single Barrel 110 Proof (Wild Turkey)
There are plenty more but this is a pretty good place to start without breaking the bank.