How long ago did you buy Pro & did you buy it from Lime Wire » Official Website & Free Download, BitTorrent « ??

If your Pro benefits are still current (ie if you bought 6 months worth of Pro, it needs to be less than 6 months since you bought it) then you should be able to download Pro again. If your Pro's out of date then your email address won't be in the database anymore...in that case you'll need to buy again to get an updated pro.

If your benefits are out of date but you still have a Pro installer saved...just copy that installer onto a CD or external drive & then add it to your other computer

If your Pro's not out of date & you bought from the official site, go back to the original email that you recieved from LW, when you bought Pro...that has a link to your download page. Or send a PM to limenathan & explain the situation.
limenathan (click on link)