There are a number of reasons why your download may be slow (or non-existent)...

1. The first files you get will be those that are on fast servers or with few other people queing to get files from the same machine. This means that the selection of files you have left to download are those on slower connections and heavily accessed machines. So your first files will come down quickly, subsequent ones will probably take longer.

2. The 2.4 Beta version of limewire will wait a much more reasonable period of time before requeries. The timer now maxes out at five minutes although it won't necessarily requery every five minutes. But it certainly won't wait two or three hours.

3. I have found that on my connection, if I leave the upload speed set at the default, it knocks out my download bandwidth (if anyone else finds this is the case then comment and I'll report it as a bug). You can decrease the upload bandwidth threshold through Tools|Uploads|Basic and the slider at the bottom. This change won't work instantly, uploads have to drop out of your queue first, but no more will be inserted into the queue until you drop below the threshold you've set. I set mine just below my theoretical limit - this seems to still allow a good upload speed while not getting in the way of my download speed

4. There is an option in LimeWire to reduce file sharing with freeloaders. A freeloader is detected by the number of files they have available for upload. If you only have none or a very few files shared you may find that other hosts are refusing your requests (file not found). I have this enabled, although my 'number of files' limit is very low.

5. You may have picked up a really poor set of peers or ultrapeers. It can happen that you connect to a really poor set of hosts and that these aren't very well connected themselves. Try looking for a different set by manually deleting connections or disconnecting entirely and reconnecting (File|Disconnect). You'll usually have to wait a few minutes while LimeWire tries to connect to new peers.

6. You can manually look for new peer sites with the file you are after by researching (or doing a new search) on the file name. The download will automatically pick up any new addresses from a search that you do. This is only worth doing when the network configuration has changed - but this does seem to change pretty rapidly at the moment.

7. There are some fairly annoying features with downloading which are due to be fixed in an upcoming version. The introduction of hashing should improve both the quality of downloads and their chance of success (theoretically files which have been renamed can still be identified as the same file based on the hash code - and errors in files will be obvious /before/ downloading).

8. Anything else is your problem. Although if you do find a way to increase download speed/completion I'd love to try it - I'm still a long, long way from 100% utilization of speed and 100% success on downloading.

Mark