How to Change Yarn Colors ~ Lets http://Crochet.com This is the best way I have ever seen to change colors. This way you have no tails to tuck in and the color change is perfect.
Picking up Vertical Stitches Along a Selvedge Edge / TK
TECHknitting: Picking up stitches part 2: picking up along a bound-off edge
'Swiss darning'; in the example above you can see how to fix a hole in a knitted cloth,
In Russian but Google Translate does a good job. Pattern is charted with very nice illustrations on how to join sections.
МК Спицы "Пришивная" планка.
Magic Knot to join yarn. A tiny knot that won't come undone.