Bad smell coming from ac when turned on 2008 tacoma

This is likely mildew in the evaporator.
Check and verify that the evaporator drain is clear. This is the rubber hose coming out of the bottom of the firewall in front of the passenger, it is aimed at the frame.
There are evaporator cleaning products available at home improvement stores that you can spray on the evaporator (might need a friend with a skinny arm). They do not need to be rinsed, simply run the AC and the moisture from the air will condense and rinse the coils. Also check and change your cabin filter. It is located behind the glove box under the horizontal trap door. It's about $15 and should be replaced about once a year, more often if you park under a tree.