UKH

Im off to Slovenia staying near Lake Bled and looking at doing a couple of via ferratas in the area. Does anyone know if a guide book is available? Ciccerone do a couple but they seem to cover Italy and France

"Mountaineering in Slovinia" by Tine Mihelič is quite a good "inspirational" guide which contains via ferratas routes, but it's quite difficult to glean exactly how difficult a particular line will be.

https://sidarta.si/en/product/mountaineering-in-slovenia-en/

The best pure VK guide I have seen is only available in german as far as I know.  I've found it pretty easy to follow generally though.  I'm pretty sure I have an older version of this:

https://www.rother.de/en/klettersteige-julische-alpen-1.html

In addition I have a mini guidebook that purely focuses on Triglav and another for the Kranjska Gora area.  Can't find them at the moment though.

There is a good bookshop in the alpine museum in Mojstrana that you should definitely visit.  Last couple of times I have been there it has had a good selection of maps and english language books that are hard to find in the UK.

It takes a bit under an hour to drive from the Bled/Bohinj area to Mojstrana, and you can add half an hour to that if you want to do anything from the Vrsic pass so you should be able to get to a wide range of stuff if you have a car.

Plenty of decent info on here https://www.bergsteigen.com/touren/klettersteig/

I've done some there if you want firsthand info - Mala Mostrojka, Prisank window, Kepa (more of a walk), Mangart.

https://www.cicerone.co.uk/the-julian-alps-of-slovenia

..and I'd recommend Triglav from Tominskova Pot, descent via Prag Route.. Great 2 days. 
youtube.com/watch?v=nMGCgtBgtzs&

Prisank window is great.  Only thing I'll say against it is that parts of the approach may have snow even fairly late in the summer.  I didn't feel the need for an axe when I did it but boots suitable for kicking steps were handy.