Honeypots are worthless in this because the whole point is the attacker not knowing what's there and seeing something fake. It's different when the attackers are in the same room and know what equipment/os you have.
actually, isn't that the point of the honeypot? they don't' know it's fake since they don't know the network, so they will be trying to hack something that isn't worth hacking. essentially they will be wasting precious time, giving you more time to set up your defense and fixes.
-Windows Xp Pro - Only computer that can connect to the Internet for patches and what not
The main restrictions of the competitions are:
-You can only use that one Windows Xp box to connect to the Internet.
If you haven't read the CCSP books cover to cover you're going to get owned pretty quickly. Unless they changed it, you're going to have a router, switch and a firewall(ASA), so know your Cisco security.
Honey pots are a waste of time, they have proved to allow the red-team more time to pop the rest of your network while you're getting everything in order(this is what ive been told many times). Work on fixing the vuln. you know about. Also, have access to full disclosure sites within your grasp at all times. Have a list of all recent/"BIG" security holes that have been found within the past 5 years. You will get your network in shambles, bascially it goes like this "some IT team has hosed up this customers network, fix it".
IDS/IPS's are you friend, people have mentioned snort... excellent suggestion. Run it inline so you can have more IPS functionality. SPAN is an option if you dont want to do that.
Spacehonkey is right, they will be attacking you from the outside.. but there is a service "counting" server where it measures uptimes(this is how the score is kept). You need to have the most highly available network, so you can't just turn off something(someone recommended this, idiot). You will get requests from your "customer" to "allow" particular services mid way into the competition so that the red-team can work on poping them.
The red-team is no joke, they are seasoned security professionals(when nationals roles around). They will not only work on accessing your network, watch out for social engineering... keyboard surfing(yes, they are allow where you sit IF you let them in!), anything.... they might try and get your drunk after the first day and weasel some information out of you.... this HAS happened before. Dont get it twisted.
My old roommates team took nationals a few years ago, and was asked to join the red-team but because of work obligations he couldn't. I have never participated in these competitions but they are very easy if you stay calm, stick with your team and have a CLEAR and DEFINED leader. If you don't, you're going to get owned.
BTW, if you get to nationals(or are in, haven't followed this stuff at all. hah) the skill level of these security guys are like this... they write 0 days during the competition.