Introduction to the Radiant Toolbar Here is a basic explanation of the tools that are included with the editor. At the left will be the actual button with it's function described to the right.
 
x axis flip:  Will flip any brush along the x axis when
selected.
x axis rotate:  Will rotate any brush along the x axis
when selected.
 
y axis flip:  Will flip any brush along the y axis when
selected.
 
y axis rotate:  Will rotate any brush along the y axis
when selected.
 
z axis flip:  Will flip any brush along the z axis when
selected.
 
z axis rotate:  Will rotate and brush along the z axis
when selected.
 
complete tall:  Selects all brushes along the x,y axis.
Grouping brush is discarded.
 
select touching:  Selects all brushes touching the
grouping brush.
 
select partial tall:  Selects all brushes along x,y axis
with discarding grouping brush.
 
select inside:  Selects brushes within a grouping
brush and then discards the grouping brush.
 
csg subtract:  Will remove contents within the selected
brush.  Used for making doors and other openings.
 
csg merge:  Will fuse brush groups when selected.
 
hollow:  Will hollow out any selected brush at a depth of
two units.  Used to make rooms and bounding boxes.
 
clipper:  Allows you to place clipping points on a brush.
 
change veiws:  Changes veiws in the wireframe window
from x,y, to z.
 
texture veiw:  Allows you to switch veiws within the veiw
window.  Trilinear to wireframe.
 
cubic clip camera veiw:  Will draw or not draw the 
 entire map while editing.
 
free rotation:  Allows you to rotate selected brush 
along any axis.
 
free scaling:  Locks or releases scaling on a selected
brush.
 
x scale
 
y scale
 
z scale
 
don't select curved brushes:  Can make life easier 
when making prefabs.
 
show patch bounding box:  Simply shows the bounding
box around and patch you create.
 
patches as wireframes:  All patches will be displayed
as wireframes.  Speeds up editing.
 
patch bend mode:  Will select varying points on a patch
allowing you to bend or twist the object.
 
redisperse patch points:  Averages out space between
brushes added to a patch.
 
caps:  Will cap any selected patch with highlighted
texture in use.
 
weld equal patch points:  Self explanitory.
 
drill down:  When any control point is selected, all 
points below will also be selected.
 
entity veiw:  Allows you to show entities in wireframe
or grayscale, ect.
This is just a basic overveiw. I'll go into more depth when actually making the first map.