I'm no expert on the Croatian music scene so I'll leave it to others more knowledgeable or interested to comment on the current music in Croatia.
One Croatian musician I know who I can recommend to expats is the guitar ace Damir 'Hal' Halilic. He's actually a friend of mine whom I know through a group of local (Kastav-based) artisans. Hal is an acoustic, fingerstyle specialist who has the knack of doing what all the other guitar pros I've heard can do, only his compositions manage to make the listening part exciting and interesting whereas the other solo guitarists make me yawn and keep me wondering how much longer before their songs will end.
Hal has hosted two music festivals in the Kvarner region (Kastav Blues Fest, Baska) this summer and is planning his 10th annual guitar festival in Rijeka at the end of October. That usually takes place at the HKD theatre in Rijeka but it hasn't been officially confirmed for this year.
I created an 'unofficial' Damir Halilic website which can be found on the website if you want to hear and see (video clips) some of his playing on his various cds. You can also catch most of his videos on youtube. I wrote a short essay about him and the production of his last cd, Mare Nostrum, if anyone wants to read it. Go to the 'general inquiry' email address on the contact page of my website under my picture and write and I'll send the essay off to anyone who requests it.
Give Hal's playing a try. He's a real Croatian talent. You may find it sounds great to you, too.