When it came time to refill my long-term medications (Lanoxin and Coumadin), I called my insurance company and asked them the cheapest way (for them and me) to get the prescriptions. They directed me to Walgreens in Florida. The cardiologist wrote out prescriptions for both for 90 pills with three refills (a year's supply), and I sent them to Florida. The meds came just fine, and I just received the first refill. The cost for this on my co-pay plan was $20 each, but refilling them locally one month at a time would have cost $30-45 each.
I too am interested in a cheaper way to get the meds, especially since my dosage has increased for the summer due to increased activity. I have a prescription for 5mg tablets, but I'm taking 7mg 3X a week during the summer, which means that I have to have other prescriptions filled.