I'm a bass player. How can I find tabs for bass?

You can filter tabs using Filter panel above the songs list (e.g. on artist page). Click "bass" in the "Instrument" column to filter out songs without bass from all the pages on Songsterr.

Filter setting will persist on all the tab list pages on Songsterr, so from now on you will only see tabs with bass tracks in them and bass track will be shown by default when you open tabs.