How can I get a list of all fonts used in an Adobe Illustrator file?
Maybe try to go to Type > Find Font.
If you are using Illustrator CS6 from Creative Cloud (i.e., Illustrator 6.1), you can go to File -> Package... . Deselect everything except "Create Report". The report will list all fonts used in the document.
(This feature will be part of the packaged software in the next major release.)
The Document Info palette will list all the fonts used.