I haven't read most [any?] of these, so this is less of a rec, and more "here are some lists to check out" (all YA or children's):

The American Library Association's GLBT Roundtable/Social Responsibilties Rountable Rainbow Project blog: unfortunately for you, sorted by age, not subject, but the blurbs are short enough that it would be pretty quick to weed through them.

From Lee Wind's blog, the Books with GLBTQ Parent/Caretaker tag.

And the Queer Parent tag from Daisy Porter's Queer YA review blog.