Im having the same problem: after updating to 12.0.1 iTunes opened in Arabic
I tried the first method in the guide, didn't impact iTunes. I tried the second method by using a friend's computer to copy the pathway to where I should have been able to change the language setting but when I got to the final screen where I should have been able to select a new language that particular menu did not seem to be available (I'll reply with a picture as I'm currently on my phone). I tried the final option of changing my country in the store - just in case, but no luck there either.
As Gary said its a frustrating problem because not being able to find the appropriate menu is making it difficult to fix. Anything we can try or any step by step instruction with pictures to change the language in this version?
Thanks