all probably a bit confusing at this stage...?
Hopefully some of this will make sense when you look at your printed chord boxes of the basics you listed (E minor, A major, A minor, E major, D major, D minor, G major, C major)
USE THE DOTS ON YOUR GUITAR NECK AS REFERENCE POINTS!!! (fretts 3, 5, 7, 9, 12 - also you should have 5, 7 and 12 on the side of the neck facing you)
As a way of practising barre chords, have a look at the CAGED method - there should be something on youtube about it.
Also have a go at playing major/minor scales as chords... sounds confusing but it's not.
Sorry my chord/tab boxes are not so very good, I had a jpeg of some old tuition notes I was going to post, but I cannot lay my hands on it.

so this is from memory...
E|A|D|G|B|E
-|-|-|-|-|-
-|-|-|-|-|-
-|-|-|-|-|-
-|-|-|-|-|-
numbers = fretted note (starting from the head stock end of the guitar)
X = muted string
0 = open string
C
X|-|-|0|1|0
-|-|2|-|-|-
-|3|-|-|-|-
-|-|-|-|-|-
Dm
X|X|0|-|-|1
-|-|-|2|-|-
-|-|-|-|3|-
-|-|-|-|-|-
Em
0|-|-|0|0|0
-|2|2|-|-|-
-|-|-|-|-|-
-|-|-|-|-|-
F
X|-|-|-|1|X
-|-|-|2|-|-
-|3|3|-|-|-
-|-|-|-|-|-
G
-|-|0|0|-|-
-|2|-|-|-|-
3|-|-|-|3|3
-|-|-|-|-|-
Am
X|0|-|-|1|X
-|-|2|2|-|-
-|-|-|-|-|-
-|-|-|-|-|-
B something

X|-|-|-|-|X
-|2|-|-|-|-
-|-|3|-|3|-
-|-|-|4|-|-
C
X|-|-|0|1|0
-|-|2|-|-|-
-|3|-|-|-|-
-|-|-|-|-|-
reverse
It's a good exercise to get you to make the shapes of the chords without having to think about it; after you get the hang of it your muscle memory will take over. You can mute the low E with your thumb curling over the neck, and the top E with the meat of your 1st finger (index)
I forget how difficult writing this stuff is as opposed to actually showing someone
Also worth noting - Barre chords are just the same as all of these shown above (with the exception of F, as it's a partial barre chord anyway), but the important thing to know it you are substituting the open strings (the nut of the guitar) with your first finger barring the whole neck
A (major barre chord)
5|-|-|-|5|5
-|-|-|6|-|-
-|7|7|-|-|-
-|-|-|-|-|-
For maximum definition - to keep even pressure over all strings, and to stop individual strings from 'buzzing' on the fretts, good THUMB position on the back of the neck is essential - In the above barre chord, your thumb should be opposite your middle finger on frett 6.
Barre chords have 3 basic shapes (for the sake of argument, there are many more, but first things first) A-shape, E-shape (major/minor) D-shape (major/minor)
E-shape (A major chord)
5|-|-|-|5|5
-|-|-|6|-|-
-|7|7|-|-|-
-|-|-|-|-|-
E-shape (A minor chord)
5|-|-|5|5|5
-|-|-|-|-|-
-|7|7|-|-|-
-|-|-|-|-|-
E-shape (D minor chord)
X|5|-|-|-|5
-|-|-|-|6|-
-|-|7|7|-|-
-|-|-|-|-|-
A-shape (D major chord)
X|5|-|-|-|5
-|-|-|-|-|-
-|-|7|7|7|-
-|-|-|-|-|-
D-shape (G major chord)
X|X|5|-|-|-
-|-|-|-|-|-
-|-|-|7|-|7
-|-|-|-|8|-
D-shape (G minor chord)
X|X|5|-|-|-
-|-|-|-|-|6
-|-|-|7|-|-
-|-|-|-|8|-
You index finger remains in place, whilst you other three fingers assume the 3 shapes (of the basic major E and A and D chord) - notice the same shapes can make a major and a minor sounding chord.
http://www.all-guitar-chords.com/ this web site shows it better than I have hehe, good for chords, scales, arpeggios etc.
If you can get someone to teach you a bit of proper music theory - about chord and scale relationships, fifths and thirds and intervals, plus some of the really basic C C#/Db D D#/Eb E F F#/Gb G G#/Ab A A#/Bb B stuff it really will make understanding what's going on much easier.
You don't need to know how to read sheet music to play guitar, but it will help a lot later on if you have some understanding of the basics of music theory, if only to name chords correctly and understand their relationships to scales and modes and musical keys.
It is something I have always lacked when it comes to reading etc and have regretted that I did not start it earlier.
Having said that... if you have a 'good ear for music' - that you can recognise one note from another and when 2 notes are in harmony as opposed to being tone deaf, then you already have an advantage. If you can hum the same note as a song you hear on the radio and recognise it as being the same and reproduce it again; is a rudimentary description of having an 'ear for music'.
Think I'm dragging on a bit now
