Well, I am by far an expert, but what I do know is that you need to get young ones, or they will most likely 'home' back to their old home. My dad feeds his pigeons a feed called cluckin' chicken, or something like that. It basically looks like scratch grain. The person we got most of them off of said he used bird seed with sunflowers in it, and he added some black beans for protein. I really don't know much on the appropriate housing, except that you need to make sure you have a trap door on their loft! We had 3 homers get out last Sunday, and in the process of getting them back in, 6 more got out! Luckily, one of the homers was hatched here, and the other two had young ones to care for. So they were in no hurry to leave their babies. The other escape artists were not homers, so they just hung out till bedtime, then went back in.
Like I said, I'm no expert, but this might get you started! We have 23 birds (counting 4 squabs) in a coop that is about 4'w by 6'l by 7' high, and they seem to like it ok. Just make sure to have plenty of roosts. A small area can seem much bigger if they have a lot of roosting space. They aren't really floor dwellers.