Mupp3t,

A Trace route is just a modified ping packet (ICMP ECHO_REQUEST). The trace route program sends a ping to your address with TTL (Time To Live) set to one. The device on the first hop receives the packet with the TTL of one, decrements it to zero and replies back to the sender with a "time exceeded". The Trace route program then examines the return packet to see what device is one hope away. A new ping packet is then generated with a TTL of 2 and sent on it's way to find the next hop.

was wondering if there was anyway to trace if your being trace routed
Monitor your ICMP traffic as you suggested and watch for ICMP ECHO_REQUEST's with a TTL of one. The default starting TTL on an ICMP packet is 255 so chances are anything with a TTL of one is probably a trace route.

If you simply want to make sure that you can not be trace routed block all ICMP or ICMP ECHO_REQUEST traffic at your firewall and the "time exceeded" packet will not be returned.

me and a friend was talking about finding out if you were being trace routed, and then change the route or break it some how.
Now that you know what you are looking for you can send back modified "time exceeded" message with spoofed information about your location to the requester, but you can't change the rest of the route since it was reported back to the sender before the last packet got to your location.