ANSWER - The book (pictured) is a good introduction to solitary craft and the magical slant is more focused on natural everyday magics than ceremonial or darker elements. It's a good read actually - written in letter form from an experienced witch to her two proteges.
This forum isn't maintained much any more but some of the information in the archives is interesting and worth exploring.
She may also find some interest in exploring Druidism which is the most nature based of all the magical paths. Some good information (and pod casts) here.
I'd also suggest some background knowledge on the elements that help form a natural path. Information on herbs, wild flowers and working with different weather elements can be extremely valuable.
Generally I would encourage her to find her own spell writing voice through the resources I recommend above. However some of the spells here might be a good starting point.