You may have noticed a difference between what you can buy on the Kentucky side of the river (essentially sparklers and noisemakers) versus what you can buy on the Indiana side (mortars that would put a Guerrilla insurrection to shame.) There's a huge difference between what's legal in each state. This is why I recommend all fireworks loving people visit their friends in Indiana for the 4th of July.
Fireworks aren't cheap. Your best bet, no matter where you go, is to pool money with friends. If you only have $20 to spend on fireworks, go down to the riverfront and watch the professional show instead. You'll get a lot better value spending your $20 on beer.
The Sam's Club on Veteran's Parkway has the single best deal on big booms. I know. I've shopped around.
You don't get the advantage of shopping buffet style like you do at Phantom Fireworks, but once you do the math, you get a lot more for your money. Offerings vary based on what they currently have in stock (I've seen it change a couple times over the season. Now that we're getting close, I don't want to taunt you with an exact product they might have replaced), but you'll typically have a sub $100 option with around 2 dozen mortars. It's off brand, but comperable to the Phantom Fireworks "New York Harbor" collection, a sub $150 option with the same number of mortars, but now they have double or triple breaks and do neat effects. Phantom doesn't offer anything like it. Then there's the $250 option with a couple 500 gram repeaters and some fountains, sparklers, and other toys. This one is hands down the best bet you're going to find anywhere in town.
They also have the droolworthy $500 mega assortment. Bring a truck. I covet this thing yearly. Heck, you could use the box as a kid's playhouse when you're done. It comes with 6 of the 500 gram (largest legal) repeaters, dozens of assorted sizes of mortars, and an ark-like pair of darn near everything you'll find on the buffet at a fireworks store. I've never had the privilege of bringing one home, so if you buy one, please invite me out to play.
The key to successful shopping at any fireworks outlet is buying in bulk. They all have incentives where you get some extras if you spend enough money. For $150 they usually throw in a big bag of very small bottle rockets. At $250 you get the bottle rockets and an assortment pack with some fountains and a bunch of neat smaller toys. Spend $500 and you get a 500 gram repeater thrown in.
Don't scoff. There are incentive plans for people who spend over $2000 - and no, those aren't aimed at small towns who sent the deputy mayor up with a checkbook. Let's assume you're on a tighter budget, though.
It's easy to nickel and dime yourself up to $150 with just a Wolf Pack (8 double break mortars), a dozen Roman Candles, and a couple of the tiny novelty items for kids. If your budget is anything under $150, go to their online catalog, make a list, and stick with it. I can't count the number of times I've seen people talk themselves up by $30 for one awesome item, which puts them $50 away from the next reward point, and then you can come home with four times as much stuff for only twice what you wanted to spend. Know you're entering a den of temptation and be prepared.
Although they're not as satisfying to shop for, year after year I find the best value for the money is in the big repeaters. If you're afraid of your little brother blowing his hands off with the big multi-mortar kits I mentioned from Sam's but you still want a really darn impressive show, this is the way to go. You'll grit your teeth when spending $100 or more on a single item, but seriously, those 500 gram repeaters are amazing. Again, chip in with friends to get a Phantom Man-O-War or a Kona Gold. You light it once, then sit back and enjoy.
In the $150-200 price range, your absolute best bet for entertainment is one $100 repeater, two $20 large fountains such as the Funky Monkey, $10 worth of sparklers, and the big bag of free bottle rockets you'll get for spending $150.
THE DOLLAR STORE
If you're in Kentucky your options are limited to sparklers and the stuff Phantom gives away as cheap prizes for low spenders. Many dollar stores carry sparklers. The one on Westport Road (next to Incredible Dave's) has a surprisingly good selection of small, safe, legal items for supervised play with kids. If you have a $20 budget, pick up a handful of cute things on the cheap to keep you occupied before the big bang at the waterfront. These are also good options if you're going to the Crescent Hill Old Fashioned Fourth Of July. You don't have to worry about crossing the river or fighting temptation to buy things you can't bring home with you.