We took our infant son to Hawaii last September from Seattle (where we live), and he was drinking whole milk at the time, so I was wondering the same things you are now... Here's what I found out and experienced:
1) I emailed SeaTac Airport to ask about the availability of whole milk. I received a quick reply that said whole milk was available from a variety of vendors once we made it past security, including any of the coffee stands (you can always double-check with them to see if anything has changed since then).
2) We ended up bringing two 8 ounce bottles of milk with us in an insulated bag (we used the insulated diaper bag that was given to us at the hospital when he was born). We didn't use ice packs, since I believe those might be governed by the same liquid and gel restrictions, but I'm not sure about that. The milk stayed cold in the insulated bag for the entire trip (6 hours on the plane).
3) TSA has relaxed the 3 oz. liquid and gel rules for things like milk for infants and medications, although it needs to be an "appropriate" amount for the length of the trip, and the interpretation of that rule is up to the individual employees. We didn't have a problem with our two 8-oz bottles for our flight, but I read an article recently about a couple (who were both doctors) who tried to bring several extra bottles of milk for their infant on a shorter flight because the flight was often subject to delays, but the TSA employee said it was too much and took the milk away.
4) To comply with the rules (and I recommend checking the TSA web site before your trip to make sure nothing has changed), you need to pull out the items over 3 oz. as you approach the scanners and show them to the TSA employees. Tell them they are for your infant. They will do a visual check, and sometimes a more extensive test (on the way back from Hawaii, I had a bottle of medicine for my son, and one of the screeners pulled me off to the side to check it for bomb residue - it was a quick procedure, and did not involve touching the contents of the bottle). To help in the event there were questions, I printed off the appropriate information from the TSA web site, but I never needed to show it.
Hope this helps!