Oh, yes, it really matters what type of seeds you plant! Seeds that are out of date, mislabeled or just plain dead can really depress a gardener. Buy from a reputable company (there are lots listed on Garden Watchdog, and you can look up any company on their alphabetical listings).
We garden in Texas, and unless your zone 8 is a whole lot different than our zone 8, I'd heartily suggest starting peppers and tomatoes from transplants, undoubtedly available at a local hardware store, big box, or nursery. Strawberries are usually started from purchased plants, and in a dedicated bed since they are almost perennial.
Sorry to be answering you on planting day, but I just saw this posting.
As to your previous question about food for your vegetables: seeds don't need food--the seed contains enough to sustain the small seedling until it gets its second set of leaves. When the plant gets its true leaves, you can start feeding lightly. If you use aged, composted manure to feed your plants you can't burn them. Many chemical fertilizers can burn if over-applied. We're in Texas, the cow manure capital of the world, but you can buy composted manure (cow, sheep, horse) at nurseries or big box stores. It is cheap, good and won't harm anything.
Good luck with your garden, come visit our farm at www.rgf-tx.com and get tips on gardening and attracting wildlife. We aren't selling anything--just sharing the joy of nature!