I'll clear this up. I is Queen's Blade Expert
"Queen's Blade" is a series of what's called "Combat Books", a spin-off of the series "Lost Worlds"
It is also the name for the entire franchise.
In addition to the original series, there is also
Queen's Gate - A supplement to the original series, these ones are almost exclusively characters of other copyrights. Such as Mai Shiranui, Noel Vermillion, Dizzy, Taki, Ivy Valentine, and other such popular characters.
Queen's Blade: Rebellion - The third series of books, and a "sequel" so to speak. In terms of continuity, the characters in them are after a time-skip. As such, there are different designs, and several new characters
Queen's Blade: Grimoire - This is the newest series of books, with only one or two currently released. The books are set in a separate world from the others, and the characters seem to be entirely adapted from folklore and fairytales. As such, we have seen a Little Mermaid, Red Riding Hood, and a Kaguya(from japanese folklore)
There is also three 12-episode seasons of the anime, along with a 6-episode miniseries. They are as follows
(Season 1)Queen's Blade: Wandering Warriors - This season covers the wide cast's journey to Gainos, capital of the Mainland, for the Queen's Blade tournament
(Season 2)Queen's Blade: Successor to the Throne - This season covers the tournament itself, and focuses on the events that happen during it.
(Season 2.5/OVA/Miniseries)Queen's Blade: Beautiful Warriors - This series serves to bridge the gap between the "classic" series as it progresses to Rebellion. Each episode focuses on the relationship between two or three of the characters
(Season 3)Queen's Blade: Rebellion - This follows the Rebellion characters, focusing on Annelotte, and the dwarf Yuit. My personal favourite season, with an expertly crafted twist at the end
There are also a few manga adaptaions, as well as two games for the PSP (Queen's Blade and Queen's Gate), that are developed by Namco-Bandai and Banpresto, and take after the Super Robot Wars series of games