The leaves on our Avocado tree are speckled with brown spots and some with tiny holes. Is this a disease and if it is what can we do for it?
This could be due to pests or disease; from your description I might suggest Cercospora Leaf Spot.
These articles have more information.
I would also suggest taking leaf samples to your County Extension Office, they may help with a diagnosis more specific to your region.
I have listed a link to help you locate your nearest office.