if they tore her sticker and it failed for evap, theres a 10 day extension waiver on the inspection report they should have given you
simplest EVAP problem is a gas cap, where you should try buying another one and making sure its on TIGHT, then going to a pep boys/autozone and have them clear the code and see if it comes back on in the next 2-4 days. if it does, theres an EVAP leak somewhere. best way to diagnose is to find someone with a smoke machine, plug it into the evap port, jack the bitch up and find where the smoke is coming from, and replace as appropriate.
if you know someone who has access to mitchells or ondemand, the EVAP code should be a P0440, and you can use their troubleshooters guides online or in print form