Some people are able to find chia seeds in person at a store near them. Try health food or Whole Foods stores. If you can’t find them (or don’t want to run around looking), you can order them online.
I wouldn’t recommend the first company I ordered my chia seeds from: The Chia Seed. They didn’t send my order until I emailed them 11 days after ordering, asking where it was. I ordered more seeds from another company today, but discovered tonight that you can get them through Amazon.com for a better price.
If you can find a better deal than Amazon, go for it! But if you order through Amazon, I would be honored if you used my DARdreams Store link (under Resources to your right). I get a small payment if you order through my store. Every little bit helps! ;+)
You can find more info and sources at Living Low Carb with Chia Seeds.