Download a file from here & see what speeds you get
http://www.magnetmix.com/video.shtml

Do a speed test & tell us your download & upload speeds
http://www.dslreports.com/speedtest?more=1

Have you used other p2p apps & if so, do you have the same problem?
Who is your ISP?

*Hope it was LW Pro that you bought, LW basic is free. Did you get it from www.limewire.com?