Raceray,
You can call Genentech (they manufacture Tarceva) and ask them if they will provide Tarceva for you free of charge on a compassionate basis. The request might carry more weight if it came from your doctor. My sister had breast cancer but no insurance; her doctor was able to obtain a costly drug for her on a compassionate basis from the manufacturer. Unfortunately, she passed away but it wasn't for lack of the drug.
Good luck.
Joan L