What is the proper way of using triple dots and spaces before/after them?

This is a matter of pure style. I've worked in houses where the style sheet called for spaces before and after points of ellipsis, and in other shops where you close up the spaces fore and aft. What matters most is being consistent once you've selected one style or the other.

My preference is for the Chicago Manual of Style method, which closes up the spaces. There are other, more subtle rules about the use of points of ellipsis, and the section here in reference to Chicago explores some of the finer nuances.

One general rule to know, which is pertinent to your examples above, is that points of ellipsis are trailing punctuation - they follow words, but do not precede them. For example:

Right: "The archeologist opened the door of the tomb..." Wrong: "...opened the door."

-but-

Right: "He...opened the door."

You might start a line of text with points of ellipsis if you are writing creative dialogue in fiction, and are trying for some kind of special effect, but that is a matter outside the realm of formal composition.

Yes, you do put a space in front of three of them, but not in front of four of them. The open questions are whether to use three or four, and whether to put spaces not just fore or aft, but between them. The short answers to those two questions are respectively

• that you use four without a leading no-break space if it is the end of a sentence,

• and that you almost always want to set them with thin no-break spaces between them, but this varies a bit depending on your face and point size.

Here follows a longer and more professional treatment. . . .

In his The Elements of Typographical Style, Robert Bringhurst writes on page 82 of version 4.2 of that book:

5.2.7   Use ellipses that fit the font.

Most dig­i­tal fonts now in­clude, among other things, a pre­fab­ri­cated el­lip­sis (a row of three base­line dots). Many ty­pog­ra­phers nev­er­the­less pre­fer to make their own. Some pre­fer to set the three dots flush … with a nor­mal word space be­fore and af­ter. Others pre­fer . . . to add thin spaces be­tween the dots. Thick spaces (ᴍ/3) are pre­scribed by the Chicago Man­ual of Style, but these are an­other Vic­to­rian ec­cen­tric­ity. In most con­texts, the Chicago el­lip­sis is much too wide.
       Flush-set el­lipses work well with some faces, but in text work they are usu­ally too nar­row. Espe­cially at small sizes, it is gen­er­ally bet­ter to add space (as much as ᴍ/5) be­tween the dots. Ex­tra space may also look best in the midst of light, open let­ter­forms, such as Baskerville, and less space in the com­pany of a dark font, just as Tra­janus, or when set­ting in bold face. (The el­lip­sis gen­er­ally used in this book is part of the font and sets as a sin­gle char­ac­ter.)
       In English (but usu­ally not in French), when the el­lip­sis oc­curs at the end of a sen­tence, a fourth dot, the pe­riod, is added and the space at the be­gin­ning of the el­lip­sis dis­ap­pears. . . . When the el­lip­sis com­bines with a comma, ex­cla­ma­tion mark or ques­tion mark, the same ty­po­graph­i­cal prin­ci­ple ap­plies. Other­wise, a word space is re­quired fore and aft. When it com­bines with other punc­tu­a­tion, in (as it al­ways does at the end of a sen­tence) the el­lip­sis, in English, is also punc­tu­a­tion. On its own, it is a graphic word. The kern­ing ta­ble must in­clude it and the glyphs it sits next to.

I should add that if you do use thin spaces to space out your dots, you want to use U+202F NARROW NO-BREAK SPACE, not U+2009 THIN SPACE, because it is a single symbol, and must not be line-broken. You probably also want to control the line breaking before the three-dot form of the ellipsis by using U+00A0 NO-BREAK SPACE there. Notice how different these four scenarios work out:

• No spaces: stuff ... here
• Font ellipsis: stuff … here
• Thin spaces: stuff . . . here
• Thick spaces: stuff . . . here

Which for me looks like this:

To my mind, the first two are both too skinny, and the last one looks too fat, leaving the third version to occupy the so-called Goldilocks position of being “just right”. It is indeed option number three, the one with thin spaces, which I have used in this posting – except when demonstrating alternatives.

Choosing whether or not to include spaces between the ellipses and the words is mostly a stylistic choice, and often has to do with readability, such as whether or not the dot closest to the word tends to disappear into the letter next to it.

As for any meaning denoted by spaces and the lack thereof used in the same work, it is so varied in fictional works and formal works alike that it is a matter of internal consistency. When reading a particular book, a space before or after the ellipses may denote a longer pause or more complete thoughts, whereas the lack of a space may denote a more hurried and out-of-breath tone. When reading another book, the space and lack thereof may seem to denote the opposite. The only way to determine this objectively, in my opinion, is to take a line of dialogue that includes one or more ellipses that makes far more sense when taken one way than when taken the other way, and refer to that when deciding what the styles on the rest of the ellipses denote. I have yet to associate changes in spacing with anything other than changes in tone or pacing.

As for ellipses occurring before a line of text, this occurs often in graphic fiction, but almost always follows a bubble which ended with ellipses. This is there due to space constraints, and the inability to put a complete thought in one bubble. Less commonly, but in more mediums, this can indicate that someone is refusing to be interrupted and continues talking over someone else.