Is there two version of ulaw and alaw encoding in audio compression?
Yes. You can choose the µ parameter freely in µ-law encoding. So, there's as many different µ-law encodings as there are possible µ; of course, only very few are standardized.
The same applies to the A in A-law.
You might want to read the wikipedia articles on µ-law and A-law, instead of just the G.711 article.