I've been trying to swipe some mangas off of eBay.com recently and I've
noticed that the mangas aren't all chronologically numbered from 1-n,
but that there are different "series?" of AMG mangas (i.e., Terrible
Master Urd, Mara Strikes Back, etc).  Can anyone list these series in
the order they were published, and how many volumes there are per
series?  Can I read each volume of the manga as its own story, or do I
need to read them in order?  

Thanks

-- 
Tony Cha