Hi lordhelpme
There is a "getting started" thread located in the Sp Ed archives.
You'll find a link to a sample letter that needs to be sent to the school district requesting an evaluation in compliance with IDEA. It's very important to send the letter via Certified Mail. School districts have 60 days to get an evaluation done, but the Certified Mail is needed to start the clock ticking.
The other links in the thread will give you an overview of your's and your child's rights regarding education for students with qualifying disabilities and Individual Education Plans (IEP).
One link that is not in the letter is the one pertaining to Protection of Children Not Yet Eligible for Special Education. These protections will kick in the second the school district receives your letter requesting the evaluation.
In that you mentioned your son is doing well academically, you'll want to read the threads in the archives regarding adverse education impact. Many school districts will say that unless a child's grades are negatively impacted, a child will not qualify for an IEP. This is incorrect information. IEPs are for children with academic OR behavioral problems.
I typically advise parents to be forthcoming with sd's regarding diagnosis, but I have to agree with others that posted in the General forum in your case for several reasons -- many that have already been addressed. From an educational standpoint, however, most school districts will interpret "conduct disorder" as "willfulness" and a student won't get the early intervention that is needed. Left untreated, behavioral problems can progress to true "conduct disorder" in the years to come. An IEP is one part of a multimodal treatment plan.
Welcome to the site.