Which exclusion list? Are you talking about the RSD exceptions?
There is no good way to do this. This is a limitation of the software that I believe they try to address in 5.x (although I haven't seen it yet). I have had to do what you are asking many times in 4.5 and I had to use MS Excel... I would select within the Exclusions list "box" and do a Select All (Ctrl+A), then Copy (Ctrl+C)... Toggle over to your XLS and Paste (Ctrl+V). Within Excel select your data and use the "Text to Columns" feature using a "Space" as your seperator. It sill require a little formatiing clean up.
Now, having said that let's back up a second. I wonder what you need this for? If you are doing an Export with the intent to do an Import into another policy there's a completely (and much easier) direction to go.
I am also aware that others have built SQL queries and gone directly to the ePO DB to get this info.
NOTE: I am assuming you are speaking of VSE exclusions? If not, please enlighten us