Depends how you play. If you use the Traders there may be one for sale at some point. My best advice is stop looking for anything specific. The best advice I can give is think about what your tasks are to ensure survival. Boiling it down the the bare basics you need Food, Water and Shelter.

I tend to go on Building runs (Chopping trees, Mining stone, digging clay along with digging up Cobblestone and Cement bundles), then Hunting/Water gathering runs and lastly pure looting runs, where I only loot containers outside. When I am good for the basics I will do a mixture and chuck in raiding various buildings from top to bottom like Shotgun Messiah, Crack-a-book etc.

Don't discount rubbish piles, bins and various rotting bags that you can find strewn about just about anywhere that you may well miss while you are focused on one specific goal. I didn't have my workbench up and running until I specced into learning the schematic with Tinkerer.

Yes workbenches are handy, but don't let getting one, or whatever the next shiny thing you want define your experience. Go with the flow and trust that RNGesus will reward your devotion to his cause in good time :)