If you are thinking of playing folk or country music it's probably easiest to start by learning chords and strumming. Also take this approach if you're not sure what you want to do on guitar. You can play a really easy song reasonably well in a week and can be playing effectively in less than a year.
Some good chords to start with are G, C, D, Am, Em, Am7, D7.
After you can play 5-10 chords, you can start practicing scales.
About 6 months in, it's time to really focus on getting a steady beat and then playing more interesting rhythms. Playing a steady beat is much harder than it seems so don't start with that (unless you're a drummer or something).
If you are inspired to learn guitar because of guitar players you've seen, it's a good idea to watch what they do (hopefully you can get some video of them) and try to do the same things yourself. This is more fun than learning from a book, although you can do that too.
Oh, and I almost forgot: If you want to play guitar well you have to have a strong grip in both hands. Get a foam grip exerciser (made especially for guitarists, under $5) and squeeze it for about 5 minutes a day. This makes more of a difference than the 1 hour of practicing you do.
Resources :
About.com - Beginner Guitar Lesson Archive
Expertvillage.com - Videos OnLearn the Math of an A-Minor Guitar Chord
Learn Various Guitars and Rythems
Also you can find teaching Guitar for beginners on YouTube, and if you have iTunes, there are plenty of Podcasts which you can learn from.
Good Luck.