My oldest was a 30w preemie after I had an emergency cs due to severe preeclampsia. He received a dx of CP when he ws 10m old, it had been suspected for a few months prior but we waited on the MRI to confirm. It is such a shock to hear that label applied to your child. I still remember, and it was almost 10 years ago.
We had a blur of therapies for several years mainly speech as he was/is atypically affected. He had a lot more problems with oral motor issues than fine or gross motor skills. With his motor skills he was able to compensate on his own much of the time.
All that to say at almost 11yo, he is a smart, funny well-liked kid who does anything he wants to. He makes all A's in school and is probably "gifted" although I haven't had him formally tested, he is in dance/theater and just finished his first show weekend for a musical that he auditioned for and got a speaking part! He was invited to and attends a boys skills class that he is not actually old enough to be in. He played little league baseball for 2 years, and is active in Scouts. Unless you knew specifically what to look for and were looking hard, you would not notice a thing different than any other kid at this point.
The best resource I can point you to is kid-power
. After all these years, it is still where I go to if I need to look something up and the Special Needs Links page was member created and is incredible. There is plenty of mainstream info as well as lots of alternate treatment. There is also an associated email list that I have been a member of for close to 9, maybe 10?, years. Some of the oldies are still around, there are a lot of new faces, but it is an great source of parental information and experience. It is fairly busy, though.
Take a while to breathe and let it sink in. Like you mentioned you are already doing what you needed to do with EI, etc. Having a dx is daunting, but what it does is open doors to the services and therapies your child may need.