It is incrediably difficult to look at a healthy looking frog and make the guess as to whether it has chytrid or not.. and this is even before we consider frog species that act as carriers (like American Bullfrogs).The only times you maybe able to tell is with caudates as they retain shed skin on the ventral surface or when the frog is in imminent danger of death or is dead... Even in those cases, the only obvious symptom may be a reddish blush to the ventral surfaces (which means it is often mistaken for "red leg" (another symptom frequently touted as a disease), viral infections, enviromental irritation or even just plain stress.
Googling images will provide you pictures of dead and dying frogs as well as microscope slides (using those as a diagnosis it is easy to have false negatives since you can miss the infection with the biopsy).
Well if he was just looking for pictures to reference and see what chytrid looked like as long as you made sure that your source and picture locations (dont just image search) was creditable searching google be just fine. note that you have to make sure your source is credible, im not saying to just do an image search and go with that
If you are trying to diagnose your frog with chytrid I would think paying for the PCR test would be the only way to get a confirmed diagnoses of of chytrid.