Unfortunately, there aren't too many out there to begin with. At least not on a popular (as opposed to technical) level.

About the best of them is Marian Coonse's "Onions, Leeks, & Garlic." And, despite my use of the word "best," it has some serious flaws and errors.

I've always found the members of this forum to provide the information I need. Certainly their experiences are more reliable than _any_ book or document I've read.

Thanks Gardenlad,
I think I tend to agree with you, that this place is better than any book out there!