To download... google search? Ok time for me to stop being harsh and here is the official website of Lagarith
and than install them.
Next steps (I use Premiere Pro 1.5, but this should be the same things):
Here you choose Lagarith or whatever. Lagarith works best with the default settings (the same should be for Huffy).
Than click "OK" and save your file.
No you have a huge file (4min 640x480 should be around 1 GB). Open this file with VirtualDubMod
and compress with XviD
How to compress with XviD stands here in the guides
Of course you can preview your .avi files compressed with the looseless codecs, but they could be hard to play (not smooth, because of the very high kbps-rate). Also you can´t uplaod 1GB on the org