Which is the best Keyword listing tool other than Adwords??
Wordtracker is a great option.
Keyword listing tools :
Wordtracker
BuzzSumo
InstaKeywords
Keyword take from search queries.
BuzzSumo and wordtracker are best one.
Don't focus too much on tools make them as a guide and rely on your target users needs and expectations.
I think you should go for Wordtracker that one is best.
Tools To Get The Best Keywords For Your Site
1: Google Adwords Research Tool
2: Wordtracker’s Free Tool
3: Google Suggest
4: SEO Book Keyword Suggestion Tool
5: Good Keywords
6: Keyword Discovery