Bryant and O'Hallaron's Computer Systems: A Programmer's Perspective has a pretty solid overview of memory allocation strategies at just the right level of abst

Bryant and O'Hallaron's Computer Systems: A Programmer's Perspective has a pretty solid overview of memory allocation strategies at just the right level of abstraction for someone who's just getting into this kind of thing: doubly- vs. singly-linked free lists, first-fit vs. best-fit vs. segregated fits and so on. That was the book I used in my Intro to Systems Programming class in college and I really loved it.