Yes Harrington on Holdem is worth a read as you'll learn some concepts from it. However it is pretty old now in terms of strategy so you will then need to read some more upto date material.
These books are the basis for the game of poker. Recently, re-reading Doyle Brunson discovered a couple of important points that I had never guessed before.
Yes, it's worth reading in that, it teaches you the solid fundamentals of tournament poker. Seeing that there's such a limited number of good tournament poker books, this is must read, at least once I'd say.
The fundamentals in this book will give you the foundation to beat freerolls and micro mtts anything higher and i believe it would leave you breakeven, this all depends on game selection though.