Logan Village vet runs a Puppy Pre School, although I haven't attended yet. Could you perhaps get a doggy door for them? Do not feel bad for leaving them outside. Even if you purchase two kennels or two crates for them, make sure they have access to grass and put the pen around that (hoping that makes sense). They should be fine around birds and ants. A lot of people get one of those plastic clam shells for children and put sand in one and water in the other (in the summer) to entertain the pups.
A run is like this http://cgi.ebay.com.au/dog-run-pen-enclosu...1QQcmdZViewItem and no they aren't on a lead or chain. You can get cheaper versions or build them yourself