Way it's created not the only issue - what is it now? for example, if someone copied an excel chart as a picture into word, it's not a chart any more, it's a picture, so no data. Have you tried the suggestion from venkat?
"but I'm also wondering if it were made in word or powerpoint if it could be pasted into excel and the data extracted"
Not that I'm aware of.
if you need more, please post back with the specifics of what you've got, not generic descriptions of the problem.
In principlle, if it's an MSGraph chart made in PowerPoint or Word, you can still extract the data. Double click on the chart, switch to the datasheet, copy the data from the grid, and paste it into Excel.