I like Helmuth's book, but I think you would probably do even better with some book that's more specific to low limit hold'em. Two books that come highly recommended (but none of which I've actually read myself) are
Lee Jones' "Winning Low Limit Hold'em":
Amazon.com: Winning Low-Limit Hold'em (9781886070233): Lee Jones: Books
Ed Miller's "Getting Started in Hold'em":
Amazon.com: Getting Started in Hold 'em (9781880685341): Ed Miller: Books (http://www.amazon.com/gp/product/1880685345/qid=1137332127/sr=2-1/ref=pd_bbs_b_2_1/104-8751163-0246357?s=books&v=glance&n=283155)
Now, since I haven't read them myself I can't say which one is better. But I have read Ed Miller's "Small Stakes Hold'em", which is sort of the sequel to the one above (with more advanced concepts and finer tuned play for winning the maximum amount of money in limit hold'em), and that one I can highly recommend. But read one of the two above first, really.
Depending on how studious you are, "Theory of Poker" (by David Sklansky) is a must-read. Not as a first book, but you shouldn't wait with it too long, because having read it will give you a better understanding of what the other books teach you, making them more valuable.
And if you're serious about limit hold'em (and there's no reason you shouldn't be) you probably want to pick up Hold'em Poker for Advanced Players eventually. That's aimed more for the higher limit play, though, and until you reach $10/$20, SSHE by Ed Miller will last you just fine.
Lots of books out there, but if you want to go with limit hold'em, this is my recommendation.