You could do this
Go to Chart|Source Data and choose the Series tab
Here you can enter actual numbers and the name of the information. Make sure you separate all numbers after the first one with a comma. Example: 1200,1500,4500,230
For a column chart, this would yield 4 columns
Replacing the worksheet references with actual numbers should give you a chart that wouldn't depend on the data
But, if you have the chart mostly formatted and the above seems too tedious, you could
Select the whole chart are
Press and hold the Shift Key and click on the Edit menu
This should give you the option to Copy Picture
As long as you don't choose to link the picture (you can choose Edit|Paste Special and make sure Link isn't selected), this should give you a picture of a chart that isn't linked to the source. You'll have to edit it as a picture, though
The first option wouldn't be very fast and second option isn't very flexible. Maybe someone else has another answer
tj