Awesome list. I'd like to add the Dark Knight Returns.
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Well done. I know it can be overwhelming because there is just so much stuff out there. I like to use the internet to find the stories I'm want to read from the past. Wikipedia is good, IMO, and DC has a Wiki site themselves. The good thing about Wikipedia is that they break it down by era and storyline so you get a nice cliff notes and are able to decide if this is a story you want to read. Plus it gives you essential info on the characters, their relationships, their alter-ego's and all that good stuff.