"My wallet was stolen," is correct and direct.
"I had my wallet stolen," is ambiguous.
On the one hand, it could imply that you were the passive victim of the theft;
on the other, it means you organised, asked or paid someone to steal it - implying that it was part of an act of deception. A novelist might write these words as the speech of a character who is perhaps deceiving a detective, spouse, colleague etc.
It's the kind of sloppy speech that could create misunderstandings.
"My wallet got stolen," is colloquial North American, typical of people with low or no education.
In colloquial US speech, "got" is frequently used in 3 different ways:
1. with an adverb,
2. in place of many other verbs
3. or as a helper word to create a passive voice.
In countries that watch a lot of North American TV and movies, these shifts in language are generally well understood. Other English-speaking countries sometimes adopt some American colloquialisms, but by no means all. The frequent use of "got" - in all three ways - is emerging.
Many Americanisms are unknown and make no sense except in US territories.
