If you're just doing normal stuff in the kitchen, the cheapest 400-grit diamond stone/plate bigger than a few inches you can find on Amazon is good enough. Onc

If you're just doing normal stuff in the kitchen, the cheapest 400-grit diamond stone/plate bigger than a few inches you can find on Amazon is good enough. Once you can get a knife sharp with that it'll only take seconds to get it ready for normal use. The next step would probably be some kind of a strop/compound for removing the bur and polishing the edge. Doing so will improve edge retention substantially. After that, it's like anything; you can get as far as you'd like into the hobby; but you'll already be able to slice off translucent tomato windows without squishing anything, so it starts mattering less for normal use, especially with the battering a knife can take in the kitchen.