l have looked through the forums searching for a solution to many peoples problems with download speeds as i am in the same boat.
i hope this info will help you to help me.

1. OS version? (eg: Windows 98) xp
2. What firewalls you have? windows
3. How much ram? 512 MB
4. Hard Disk space available? 160 GB
5. Connection type? (eg: dialup, broadband, cable, etc.) broadband
6. Modem & router brand name & model numbers? GlobespanVirata USB IAD LAN Modem
7. Where are you trying to connect from (house, appartment complex, school, student accomodation, work, etc.)? house
8. What version of LimeWire (LW) & Java do you have? (Go to LW's menu Help>About LW...) Will show both LW & Java version. LW is 4.12.6 pro/J 1.5.0_10
9. Who is your ISP provider (Internet Service Provider)? TalkTalk
10. Do this simple test for us. Using your browser go here: http://www3.limewire.com:6346/ The page should say 'Your test worked!'. What happens when you go there? Your test worked
11. Are you sharing the connection with other computers or p2p sharing programs? If yes, please give details of set up. No
12. Is this a your 1st try at LW or is this a new problem with an experienced user. used LW on dail up before but i am still a novice
13. Do you see a brick wall in front of the blue world icon at the bottom of LW's interface? yes

my DL speed is 8KB/s sometimes it will go up to nearly 30KB/s (KB not kb)