Dear,
I wokred at University of Alaska as J1 researcher. I stayed in USA 84 days in 2006, 347 days in 2007 and 89 days in 2008. As per treaty I was exempt from paying any tax for 2 years (Treaty article 22). In 2006 and 2007, I filled 1040 NR-EZ and 8843 form.

Do I need to fill same form in this year or do I need to fill different form. Anyway I am filling this time from outside of USA.

The two years tax exempt means 2 calender years or two tax years. I entered in USA in OCT 2006 and leave March 2008.

Please advice me what forms do I need to fill.

With regards,
Snehamoy

Which country?

I am Indian resident and presently staying at Canada

You will file nonresident tax return and Form 8843. The exemption is for a period of two years.
Read India U.S. Tax Treaty