Where can I find good docs/tutorials on UDP. Also, here I''m assuming that UDP would be the preffered level at which to handle large amounts of data between several users. true?

If you want to send large amounts of data, and you want to guarantee it all gets to the other end, and you''re not too worried about latency, use TCP. UDP is preferred when you wish to keep latency as low as possible, but you''re not to worried if the odd packet (around 5% give or take) don''t reach the other side. Also, UDP datagrams have a maximum packet size (but unfortunately i can''t remember what it is right now!) which is much smaller than TCP, so for sending thing such as large files where you want to guarantee that it all gets there (without extra coding) use TCP.
As for docs and tutorials...beej''s network doc (can be found on this site) is really good for general socket programming, including UDP, if you''re actually looking for a technical spec on UDP (rather than coding) i''m not exactly sure, but i think if you look through the articles on this site, there are 1 or 2 that get into the technical side of how the packets are built/transmitted etc.

Yeah, I already found Beej''s doc. Latency is an issue here I think so UDP is probably the way to go. Thanks for the warning about the packet size though.