Yes, it's really hard to find "cheap" yet good food. Appropriate food for cats are just meat. Know that, remember it well. Anything else put into cat food that isn't, like grain (rice, corn, wheat gluten), or vegetables (potatoes, carrots, peas, zucchini, kale, even tapioca) isn't appropriate for their diet. So right there, it eliminates pretty much ALL dry food. Getting expensive, yes?
But you ARE on the right track by giving them wet food for starters! Yay! Wet is the way to go, even if you ARE feeding them Friskies. I think a lot of people would direct you to catinfo.org just to gain knowledge about food while keeping your cat's health in mind. Take your time reading that, in small bits if you have to, as it covers many crucial but basic things that a LOT of cat owners don't know about. It's a fantastic new beginning for you to wonder about cat food, and learn what you can do to enrich and extend your beloved feline's lives!
Welcome to the world of cats, lol. :catsm