Firstly, let's talk about the guitar itself.
When it comes to choosing between acoustic and electro-acoustic, there really is no difference in playability, save for (of course) that electro-acoustics can be directly plugged into an amp. And even then, sometimes you get better quality just by putting an acoustic up next to a mic. Now choosing an acoustic and electric are somewhat different, because in the end an electric is mostly controlled by external controls (amps, pedals, etc.) while acoustics/EAs (for electro-acoustics) actually require a certain shape in order to properly make sound. You have to decide what sound you feel is best for you - mellow and soft? Bright and bitey? Or somewhere in between? A lot of this is based on going into your store and just playing (for this, just play a G chord - Google it), and getting a good feel for the instrument. My personal favorite guitars are Guild guitars and Taylor guitars. I find that Taylor makes guitars more in the middle, and Guild makes guitars more on the bright and bitey end.
In terms of accessories, you'll definitely want to get a tuner. Get a clip-on tuner, because they're usually the smallest and they clip directly onto the instrument, giving the most accurate reading. Of course, if you have a smartphone, you can probably get a free tuner (though not as effective).
Also, buy a trigger capo. The ones where you screw in manually are generally cheaper, but they're a pain to put on and take off. Trigger capos are just put on/put off, and when not in use you can clip them on to the headstock. In case you didn't know, capos basically change the relative position of the nut, so you don't have to play barre chords.
Of course you'll want to get a few picks. As a beginner, choose thinner ones - not as good for intros and riffs, but good to get started on strumming.
Get a guitar cleaning cloth, for obvious reasons. Note that you can also use this to clean your strings.
Get a peg winder when you need to change strings. You don't need one, but I can tell you from experience that it's a HUGE pain if you don't have one. Try to find one with a built-in wire cutter.
You could get guitar polish, but you probably won't need it for a while.
One more thing that's nice, but not required:
A slide is essentially a metal or glass tube that goes on your finger, allowing for an entirely different style of play. It's generally more difficult, so don't bother getting one now.
Resources:
Use songsterr.com and ultimate-guitar.com for tabs - UG is good for quick tabs, and Songsterr is good for tabs with rhythm. Of course there are other out there, but these are (I think) two of the most extensive databases.
Marty Schwartz on YouTube has a bunch of good beginner videos. He's on like three different channels, so check them all out.
Techniques:
Barre chords, which are chord shapes that can be played anywhere on the fretboard
Scales, which are also shapes that can be played anywhere
Improvising, which is linked to learning scales. This will not come quickly nor easily, so be patient
Fingerpicking/fingerstyle, which allows for more solo-type songs (Nothing Else Matters, Blackbird, Tears in Heaven...)
Slap style (usually meant for bass). For guitar, this is kind of a subset of fingerstyle, but whatever. If you can learn this, you have a skill that many guitarists do not.
Also, I'm gonna guess you follow AH? :D