In addition, many of the companies who make antidepressants have patient assistance programs that provide medication free of charge.
Poster rliz offers some good advice.
I am fortunate in that I personally attend a local clinic that has a sliding scale payment policy and pay only $11 per visit to see a psychiatrist. He often gives me sample medication for several months at a time for nothing.
Walmart and several other retail establishments offer generic medications including some antidepressants for as little as $10 for a 90-day supply.
Non-medication treatments for depression usually follow standard health advice, such a balanced diet and regular physical activity of some kind.
If you are a reader, I recommend Andrew Solomon's "The Noonday Demon" and David Burns "Feeling Good" to educate yourself about your presumed condition.