At this point, there were 2 possible courses of action. In many cases the concrete for the footer is poured first, with rebar placed so that they run up through the foundation walls, joining them to the footer. I wasn't sure if that was the best course of action or not, so I decided to buy the rest of the block I needed and set the foundation walls into place, just to make sure everything lined up properly.
The way I'm stacking my block does not require mortar, because the blocks are all going to be filled with concrete anyway. This is called dry stacking. So I'm just setting everything into place at this point, and can pull it up again if I find that I've done something wrong.
At this point I have the footer in place and I have pieces of rebar sticking up everywhere that are going to go up through the foundation walls. The pieces of rebar sticking up are very dangerous, because it's all too easy to poke yourself in the eye with one of them. You can buy red caps that go over the tops of the rebar for protection, but I skipped that and just made sure to be extremely careful. I set the block for the foundation walls into place, lifting them over the pieces of rebar where necessary (every other block). I staggered the corners so that the blocks interlocked properly, just as you would do if you were using mortar. I found that with the foundation walls perfectly square and the correct length, they did not quite sit perfectly in the middle of the footer. They were off slightly, but it was not a problem. There was still plenty of support, and once concreted into place, this foundation was not going anywhere.
So now I had the whole foundation sitting where I wanted it, but I wasn't sure what the next course of action was. I felt I needed a reality check at this point, and I wasn't sure if the county inspector needed to see the rebar in place before I poured concrete. My inspection card did not have a section for rebar inspection, but I figured it couldn't hurt to call and ask.
So I called my community development office and left a message asking if the rebar needed to be inspected before I poured concrete. The inspector came out the next day. This was my first time meeting the actual building inspector, and I have to say he was about the nicest, most helpful person I have ever met. He told me that everything I had done so far looked great, and then asked what I was going to do next. I told him I wasn't really sure, but I thought it was time to start buying bags of concrete and filling in the ports. The inspector did some quick math in his head, determined that I needed about 5 yards of concrete to fill the ports, and asked if I realized how hard that would be to do by hand. He also said that the cold joints that would be created would create a weak foundation. His advice was that I price out having a concrete truck come out and fill the ports. It would be finished in an hour instead of weeks, and would be much stronger because there would be no cold joints.
We also discussed the type of anchors I was going to use and how they were going to be spaced. As the concrete is poured, the anchors for the actual garage walls need to be set into the wet concrete, so it was important to have that figured out before the concrete arrived.
After he left, I made some phone calls and found a local concrete company that sent a guy out for free to look at my work site. He said that the best way to fill in the blocks would be to use a conveyor truck. It looks like a normal concrete mixer truck except that it has a large hydraulic conveyor folded up next to the mixer drum. The conveyor truck would only need to back part way up the driveway, and the conveyor would be moved around as needed to fill in the foundation. This is a lot easier than trying to fill the foundation from normal chutes off the back of the truck, especially in my small building site. We worked out a price which was reasonable and I called the office to set a date for delivery.