http://www.8notes.com/guitar_chord_chart/C.asp
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Berklee Teacher / Luthier & Studio Guitarist

Find the noted fret on the tab staff. If a "4" is noted over of the E string line, you will push the E string onto the fourth fret down from the headstock of the guitar.

Follow the tab from left to right. The tab staff is arranged horizontally so that it can be read like a book.

Play the notes that are aligned vertically on the tab at the same time. Each vertical alignment of notes is one strum or pluck of the guitar.

Moving "up" on the fret board means moving your fingers closer to the body of the guitar.

A string on the tab staff noted with "0" means that the string should be played open, or without any fret.
http://www.guitarlessonsplay.com/how-to-read-guitar-tab/
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If you ask me, it’s much better to ACTUALLY LEARN MUSIC than just memorizing a bunch of inherently meaningless shapes and fingerings. At my very first guitar lesson, I walked in and said "this is a G major chord, tell me why." This caught my teacher a bit off guard, but the next week he brought me a chart that EXPLAINED everything. Then I could figure out how to play pretty much any chord you asked me to play. It propelled me so far ahead of my friends (who had been playing guitar for the same amount of time), that I have no doubt it’s the best thing to do. I always try to help my own students the same way.

So….
http://www.lukesniper.net/?p=181
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Turn your guitar around so that you’re looking at the strings and point the headstock towards the ceiling. See the resemblance?

Vertical lines represent the strings, horizontal lines represent the frets, the thick horizontal line at the top represents the nut. The dots are where your fingers go.

It’s pretty simple.
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It depends on the song. Sometimes you will be able to play it just right without any problems. Other times you won’t be able to do so.

Drop D is an awesome tuning though, and there are a lot of interesting and unique things you can do with it that you can’t do in standard tuning. I recommend you learn some stuff written for drop D… and by that, I DON’T mean a bunch of crappy metal songs with a bunch of one-finger power chords. That’s just lousy guitarists being lazy. Drop D is awesome and has been around way longer than those bands. I used to use drop D all the time when I played classical guitar.
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Chord charts are easy once you learn then and they are quick to learn. Rather than write a bunch here, look at this article. It has diagrams and pictures to make things clear.
http://www.guitarchordsmagic.com/guitar-chord-charts/how-to-read-guitar-chord-charts.html

Since you are a beginner, I will give you a link to a good and simple article about how to read tabs. That is the other form of writing guitar music you will need to learn. It also is easy to learn.
http://www.howtotuneaguitar.org/lessons/the-basics/how-to-read-guitar-tab/

Later,
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