Betsy, figs are prone to a rusty fungus in humid weather. Not much you can do against it, since most of the effective systemic fungicides are not usable on edibles. Best thing would be either baking soda and water spray (1/2tsp. per quart a couple of times per week is needed since it is so soluble) or Neem oil spray. Both will prevent the fungus from spreading, but won't cure what's already there. IF the whole tree is already spotted, it may be too late. Remove any leaves that have a lot of spots, and start spraying! Be sure to take away all the dead leaves in a bag and throw them in the trash, not compost or they'll re-infect the healthy leaves.
That being said, neither kept my little fig from completely de-foliating last year when I caught the fungus too late. So far this year I started spraying with baking soda very early, and it has lots of healthy green leaves again, but we're just getting into summer. I have one fig on the tree. If your fig loses all its leaves, it very likely won't die and will leaf out later in the season, when you'll have to try to spray diligently to prevent re-infection.
As for netting against birds, you can buy bird netting online fairly reasonably. It is a royal pain to try to net the tree effectively, (not to mention removing the net later) without about 6 people to help you. Then the net is a hazard to other animals besides being pretty ineffective against birds and squirrels. I just removed the netting from my lychee tree, and found a nice black snake - a very beneficial garden species - horribly entangled in the netting. It took my neighbor's two daughters and me about half an hour to disentangle him. We cut him free, then he promptly dove right back into the net for cover, getting all tangled again because his head and forward part of the body fit through the holes in the net, but the rest of him was too fat. We did get him free, but what a trauma to us all.
