welp. I'm glad to see that I was right. Jen had a very good writeup in her ASCII article. I would like to point out that windows for quite some time has come with the very table you have been looking for. It is called CHARACTER MAP. in WINNT it is an optional install and if installed is usually in Start \ Programs \ Accessories \ System Tools \ Character Map.
If I do Start \ Run \ Charmap that seems to get it up and running as well.
Now if you look very carefuly you will see that at the bottom of the program it gives the character code, and most often the shortcut keystroke (ALT+0123) The interesting thing is the shortcut keystroke is not listed for all characters that you can see.
Open up word and select ARIAL font. ALT+0247 gives me a ÷ simbol. in fact I used the shortcut to put it in here. BUT if i use something like SYMBOL font it gives me a . now this was the exact same shortcut. I changed the font. the font is mearly a collection of vector images that is mapped to codes. any font could use any code to map to any symbol.
conclusion: the shortcut method in windows ONLY WORKS IF YOU KNOW YOUR TARGET FONT. Maybe sarah can tell us what the standard font browsers use to render web pages?