Slovenia infos

Hi, I'm Gianluca and I'm going to do my first alone-bike tour this summer. Could you give me some advices?
I plan to leave from Padova (north-east of Italy, near Venice) the second part of July (or August) to go to Slovenia. Are there some places which have to be seen? I read the Triglav national park is very nice, have you ever been there?
And is wild camping accepted? I know it is illegal, but do they get very angry if they find you?
Ciao!