Duh! That's the key to pronunciation here :) It appears those words are spelled correctly but pronounced incorrectly by many native and non-native speakers alike. I am by no means a Sanskrit or English expert but I believe the "a" at the end of many of those words is pronounced the same way as the vowel sound in the word "duh" (with less emphasis on the h) For example, Arjuna where the last "a" is pronounced the same way as the "a" in the word "Krishna" is correct. (ie Arjun-uh, Krish-uh). Like wise for Mahabharat-uh, Yog-uh etc Which is what I the original intention in spelling it that way was.If you look up most dictionaries thats how the IPA pronunciation is listed. Just a thought.