I forgot to mention easy answers to your questions.

How to reduce airfare?
1. use miles to fully pay for or take some cost out of flights
2. set fare alerts at a site like kayak.com and monitor flight costs if paying cash
3. use a credit card that you can use miles/points to pay for flight costs after you book
4. always compare multiple sites and prices and always compare to the actual airline site. sometimes the airline site ends up being cheaper
5. see if you can add flights onto your land package at a reduced rate