She
shouldn't have needed a biopsy to diagnose ringworm (hope it wasn't expensive!). Although it's not completely accurate, ringworm is usually diagosed by the simple method of shining a black light on the dog (the lesions will glow). Takes about a minute. Which means that treatment can begin a few minutes (not weeks) later.
Treatment by antifungal cream (of which lamisil is a good one) is the best and least invasive way to get rid of it. I don't think it's a great idea to let the dog lick though (pretty sure there'll be a warning on the packet about not ingesting it). You can get topical creams from your vet too - but they're not actually any different from what you'd get over the counter at your pharmacy - except possibly in price
For severe cases - meaning
generalized, where the lesions are covering much of the body (which I don't believe is your case) then medicated shampoos are a more appropriate treatment, followed as a last resort by dipping. And those are
different dips to those for mange.
Since your dog is recovering from mange, I wouldn't even consider dipping her. That's just going to weaken her immune system further, and make her vulnerable to a recurrance of the mange (which is far worse than ringworm). Try the gentle option of topical cream first

It's usually the successful one anyway.
Here's a short article on ringworm that you might find useful:
http://www.peteducation.com/article.cfm?cls=2&cat=1557&articleid=471