Searching with wildcards

I wish it were easier to find out the wildcards that can be used in the library's catalog. For future reference (mine or someone else's), ? can substitute for a single character (the example in the OPAC help info, if you can manage to find it, is wom?n, which will find instances of "woman", "women" or, not mentioned on the help page, "womyn"), while $ is used for truncation (educat$ finds "education", "educate", "educates", "educating", etc.). I don't often use substitution, but I love truncation. According to the help page, you can also add a number after $ to limit the number of characters matched. I've never done this before, but it has great potential if you're searching for variations of a very short word.

A day or two ago, a student who had been conducting individual searches with every variation of words beginning with "educat" was very grateful when I showed him how to use $ in our catalog. Of course, then we moved on to Academic Search Complete, where truncation is accomplished with an asterisk. I tried to show him how I was able to find out which symbol is used for truncation, but I have to say, although I, personally, had an easier time with EBSCO's help pages than with our catalog's help pages, it can still be a little daunting.

Web of Knowledge includes, at the bottom of its search fields, examples that use asterisks, which is what it uses for truncation, but there's nothing near those examples that explains what the asterisks do. So, while I applaud them for trying not to bury their truncation information in their help pages, they're effectively still burying the information in their help pages. Just like everyone else.

Is there a database/catalog/etc. out there that communicates wildcard information in an easy-to-understand, easy-to-find, non-daunting way?