I'll post you some pics of my loft tomorrow.
What do you want the pigeons for? Food? Racing? Or just pets? I've found that if you can get tame ones they make fantasic pets, but if you want to bring it inside every now and then you'll have to clean up all the mess they make Racing is a waste of time - it isn't very rewarding, because you never see them racing, and you don't get any pleasure out of it if you don't win. If your not winning you are just wasting your time and money on it. If I were you I'd go for fancies - they are very beautiful and are fun to keep and breed
You don't need a big aviary - in fact, avoid it! You want something small so the birds are easier to catch. The bigger you go, the harder they are to catch, and the more skittish they become. The great thing with pigeons is that they can be let out to fry around the neighbourhood, and they will come back into the loft for a feed when they are done.
Feed them twice a day - once in the morning and once in the evening, and place the food in their bowl just after you have let them out - then they'll come in quicker because they are hungry
You need to make sure the loft is always moderately clean - if you get them used to having it completly clean, you'll have healthy birds, but if they get a disease they'll go downhill very fast. Always make sure they are exposed to a bit of mess, to help build up their immune system so they become hardier and more disease-resistant.
They also need to be regulary drenched - every two or three months is good. I give each bird half a Trichozole tablet and two or three drops of Moxidectin on the back of the neck (make sure it goes on their skin). I put Baycox in the water according to the packaging.
Any other questions just fire away