I think,.. the Library. Just went there myself today to pick up Harrington on Hold'em as I had it ordered in from out of town.
My best advice,.. loan out a bunch of them from the library, then buy whichever one's ya figure you'd like to keep around.
Doyle's SuperSystem is also a must read in my 'books'. Maybe not #1 but a good base to start with.
I also liked reading Helmuth's books, although many don't go for them. I think they're good to get ya started for sure.
Okay,.. here's another book that you don't hear of very often, fairly simplistic in nature but very cool,... The Complete Book of Casino Poker by Gary Carson,.. and The Complete Book of Hold'em Poker. Both are cool,.. could get ya goin' in a good direction (I found them to be very helpful (useful) during my first few books I read. Not alot of time talking about implied odds
, pot odds
, implicit odds, etc. etc.,.. .a bit, but not alot. Just some decent thinking in the way of poker.
There are just a ton out there though eh. Some repetitive of others.
Also a couple out there that are based strictly on internet poker, from 'online tells
' to how to win online SNG's, etc. Some valid info. in each I've read but not the be all and end all of books by a longshot.
seriously,.. 'the library',.. I've taken out Theory of POker, Doyle's, Harrington, etc.,... some I've just renewed over and over and over and over again. One I've had for well over 6mos. and just renewed it again today, lol. It was one day overdue so I had to pay out the big $0.15 first, hee hee. Just the price I like to pay.
Some books for sure though you will want to buy so you can keep it always (highlite it, etc. or whatever you like or want to do)