Diamond is Unbreakable is the fourth part of JoJo's Bizarre Adventure. In this part, Araki completely changes the art style, and things definitely take more of a turn for the absurd than they ever have before. There are also tons of band references, just like the first 3 parts.
That being said, there's really no reason not to expect that at this point, especially when this part is a murder mystery about a killer based on David Bowie. While there are band references aplenty, let's go ahead and go through some of them you probably missed while you were watching.
10 Highway Star
Highway Star, or as it's known in the localized version of the show, Highway Go Go is a stand used by Yuya Fungami. The stand is able to chase people for long distances, and once it hits its target, it's able to drain the lifeforce of the one it's attacking. It's an ability that was used really effectively to attack Josuke, but in the end, he prevailed. Highway Star is named after a song of the same name by the hard rock and heavy metal band Deep Purple.
9 Super Fly
Super Fly is probably one of the most interesting stands in the show. It's among the first to be introduced as an automatic stand that's bound to someone, which means it works on its own and becomes connected to one person.
The stand itself is an electrical rower that traps anyone who enters inside it until another person enters, and it's named after an album by Curtis Mayfield with a slightly different name, Superfly.
8 Echoes And Its Acts
Echoes is Koichi's stand, a school mate of Josuke's who gets hit with an arrow and discovers that he's survived the attack and gained a stand ability. His stand is called Echoes, and it actually has multiple abilities, albeit at different times.
It has a three-act structure, just like the song the ability is named after, "Echoes" by Pink Floyd, with each iteration of the stand having different powers. The song "Echoes" is over 20 minutes long, because... it's prog rock.
7 Enigma/Misterioso
This is one of those weird double reference stands, thanks to the localization once again. Originally, the stand was named after the German electronic band Enigma, but once they decided to localize it, the name became "Misterioso," which is a song by the jazz musician Thelonius Monk.
The stand belongs to the character Terunosuke Miyamoto, and it can turn anyone it encounters into paper. While it doesn't seem exactly like a useful ability, he does manage to pull it off a couple of times.
6 Angelo
Angelo is a bit of a weird reference to make because it almost implies influence from a show that was running concurrently to the manga. David Lynch's Twin Peaks was airing while the manga was being released, and the first major enemy that Jotaro and Josuke encounter is named Angelo.
While not exactly a band, the composer for Twin Peaks is named Angelo Badalamenti. Many people have cited a few similarities between the two IPs, but any more than that is just conjecture. Angelo is a stand user who holds the stand Aqua Necklace, introduced early in the show.
5 Harvest
Harvest is a stand that's used by Shigechi, one of the first victims of Kira that we actually see lose his life.
The stand manifests itself as tons of little bug-like creatures that can be controlled by Shigechi, usually collecting small items like coins for him to spend on whatever his little heart desires, or, if he really needs them to, they can also overwhelm an enemy due to the sheer number he's able to bring them out in. The stand is named after a classic album by the folk artist Neil Young.
4 Achtung Baby
Perhaps one of the strangest characters in this arc is Shizuka Joestar, who is a small infant found on the side of the road in Morioh, and was subsequently adopted by Joseph Joestar. The baby episode is definitely a bit of a filler arc, but it's an interesting little detour for the show to take nonetheless.
After the baby is adopted and that whole fiasco is over for our boys, we usually only see her again being carried around by Joseph. The stand, Achtung Baby, is an ability that allows the baby to become invisible, and it's named after the album by arena rock band U2, best known for the hit single "Mysterious Ways."
3 Love Deluxe
Love Deluxe is a stand wielded by Yukako Yamagishi, named after an album by the R&B artist, Sade. Sade has had a few radio hits, but it's not really the music that Araki usually went for up to this point, so this one is a bit of a surprise.
The stand itself is also quite an odd ability, being tied to Yukako's hair. The ability generally works to create large, powerful, and durable tendrils that can be used in combat either to ensnare people, whip them, or just pick stuff up for her.
2 The Hand
The Hand is a particularly goofy one. This one isn't even really a reference so much as it is just kind of a bad pun. Okayasu, one of the best friends of our protagonist Josuke, is the stand-holder, and the ability it has is to basically just throw whatever his right hand touches into the void.
He has no clue where it goes, and no one else does either. The ability is actually named after The Band, a rock band with a pretty apocryphal history. The explanation given for their name is that after they finished supporting Bob Dylan, they kept going with The Band, rather than being called Bob Dylan and the Band. It's bit of a dad joke for sure.
1 Prince
This one is kind of written all over the main character, but until someone really spells it out for you, it's a little hard to notice. The Prince reference, perhaps the biggest one in this arc, is that Josuke himself is modeled after Prince.
This becomes particularly apparent when you start to look at his color scheme, which isn't only a reference to the color that Prince generally wore, but also to Prince's album and film, Purple Rain. It's also clearly stated in the show that Prince is Josuke's favorite artist.