The even have some hummingbird and bee mixes which have hundreds of seeds for the same $1.00!
While some seeds can be quite expensive, here is a source I am testing out that seems very inexpensive – Dollarseed.com
Each packet costs $1.00.
I just bought five packets for $7.75 which includes postage.
They even put in a free package of lettuce seeds.
The marigold and zinnia germinated in 3 days.