This tutorial will cover the basics to the advanced modeling features and techniques in Blender.  The Basics section is for completely new Blender users and the Advanced section is for the Blender users who want to take the next step.

The Basics of Mesh-Modeling

What Things Are:

First off, I will explain what things are when modeling or editing a mesh.  When you first open Blender, you'll see a cube, lamp, and a camera.  In the 3D-Space, select the cube(Right-Click) if it's not selected already.  Then press(Tab-Key) to go to "Edit-Mode"  Edit Mode is the modeling and editing mode for meshes(Shapes)  There should be four dots colored yellow(This means there selected) if there pink, then there unselected.  press(A-Key) to select all.  These dots are called "Vertices" or "Vertex" if there were one.  The black lines connecting the Vertices are called "Edges" and the pink space filled is called a "Face"  Press(A-Key) again to deselect all.  Also press the(Z-Key) to go to "Wire-Frame" mode.  This is what it should look like:

Selection Methods:

Rotate the 3D-Space by holding(Middle-Mouse-Click) and dragging the cursor in the 3D-Space.  Get a feel of the 3D-Space and then continue reading.  Select the Vertices by(Right-Clicking) them.

To select multiple Vertices, hold(Shift) and select more than one.  By clicking any one of the arrows and dragging will move the selected Vertex/Vertices.  The next type of selection is called "Box-Select"  Box Select is a method used to select a lot of Vertices at once instead holding shift for ten minutes.  Deselect all(A-Key) and press(B-Key) once in the 3D-Space.  You will see a cross in the 3D-Space following the cursor.  Left-Click and drag to make a box/rectangle shape.  Then drag across some or all of the Vertices, then release to select whatever is in the box\rectangle.

This technique is very useful when there are a lot of vertices but you don't want to select all of them.

The last but not least selection type is "Circle Select"  After your out of Box Select mode, press(B-Key) twice to go to Circle Select.  Obviously, it's a circle(That you can change the size by scrolling the (Middle-Mouse-Button)  By Left-Clicking and dragging across any Vertices will select them.

This selection type is useful when the Vertices are in tight corners.  Holding the Shift-Key, Box Select, and Circle Select are the most common ways to make selections in Edit Mode.

Advanced Mesh-Modeling:

Subdivision Techniques:

Ok.  In the Buttons window below the 3D-Space, theres a lot of small buttons for editing in Edit Mode.  Select all(A-Key) and locate a button called "Subdivide" in the "Mesh Tools" window.

Click it once and you should see something like this:

It divides whatever is selected into fours.  Now, press(CTRL+Z) to undo and then find a button called "Fractal" somewhere next to Subdivide.

Once you click it, a dialog box will appear called "Rand fac" for "Random Factor"  Set the number to 25 and click OK.  You'll see that it subdivides in a messy way.

The same amount of Vertices are created but placed in random places.  Random Factor is how dramatically there misplaced.  Subdivision is useful for just regular modeling and Fractal Subdivision is useful for modeling landscape, rough surfaces, water, etc.

Extruding & Filling Features:

Extruding and Filling are very important when modeling a mesh.  To Extrude, select a Vertex on the cube and press(E-Key) then move the cursor to see the newly created Vertex.

By selecting multiple Vertices and then Extruding you will be promted with a menu.  Theres two options if you've selected Vertices and Edges only and theres three options if you've selected one or more faces.  "Only Edges" extrudes edges with faces filled.  "Only Vertices"...Hmm, I wonder...Only Extrudes Vertices.  And then "Region" Extrudes but deletes the original face and extrudes out with another face.  And then when you select a whole object(In Edit Mode) another option will appear "Individual Faces" 

This is what happens when you select more than one Vertex-|

Just Experiment with the different options on the prompt menu.  You can come up with some awesome stuff.  Now to Filling.  Filling is very important and I'm sure you guessed what it is.  Deselect all and then select one of the corner Edges of the cube and then extrude the Vertices to the left of them with Edge Select.  Then select the three vetices that represent an empty hole.  After that, press(F-Key) to fill in the hole.

So now you know how to extrude and fill.  The feature I probably use the most is is the fill function.  But both are very important when wanting to create a model.

Cutting:

Cutting is an often used feature for modeling and subsurfing very "Artificial" objects.  But you can use it on whatever you want.  I cut just to fix some subsurfing displacement or when I'm modeling the actual shape.  When your cube is normal, press(CTRL+R) and point the cursor somewhere over one of the faces of the cube.  A pink line should show up around the cube.

Left click and you'll see that it creates edges where the pink outline was!  Scroll up to create multiple lines for cutting the mesh:

Cutting is very useful for basically......anything.  The reason why it's called cutting is becuase your splitting the faces an half or dividing them "Cutting"  You would think though, it would seperate the two faces becuase cutting in real life is seperating one object from itself.  But remember this feature, As it can save your life sometimes!

The Header:

The middle header is very useful when editing a mesh.  It has very advanced functions for selection, transformation, display, etc.  Look at the image below and experiment with the different features.  Espacially in the "Mesh" menu.

In the Mesh menu, go to "Transform" and select any one of the options to see a very wierd result.  The Mesh menu basically has everything you need to model a mesh.  Also try out the different selection types(Edge Select and Face Select)  All I recommend is to experiment with the header.  That's how I figured most of everything out.  And make sure you read the tooltips too.

Well, that about does it for Mesh editing(Besides Sculpt Modeling) But that's another topic.  I hope this tutorial was useful to you or helped out on anything you were having trouble with.  If your stuck or have a suggestion, please go here: http://www.freewebs.com/lojimekworks/contactme.htm

Good luck and happy blending!