Meta-Characters, Special Characters

[Will <schimpanski@gmx.de>]

Hi,

how can I find the an overview on how to enter meta-characters
(e.g. esc, return, linefeed, tab, ...)
a) in a regular buffer
b) in the minibuffer when using standard search/replace-functions
c) in the minibuffer when using search/replace-functions using regular 
expressions
d) in the .emacs file when defining keybindings

As far as I can see in all those situations entering meta-characters is 
addressed in a different way which I find confusing, e.g.:
a) <key> _or_ C-q <key>
b) C-q C-[, C-q C-m, C-q C-j, C-q C-i
c) \e, \r, \n, \t
d) (define-key [(meta c) (control c) (tab c)] "This is confusing!")

Furthermore, they are displayed in a different way,e.g.
- actual, visible layout
- ^E, ^M, ^L, ^I
- Octals

I would be happy about pages summarizing such information.
Any references available?

Thanks in advance,

Will