Can you find kelp noodles in major grocery stores?

Yes, you can find kluski noodles in grocery stores, especially in areas with significant populations of Polish or Eastern European descent.

A kluski noodle is a medium wide, dried egg noodle, often with a coating of unblended flour on the exterior, that more closely resembles home-made noodles (when cooked) than modern mass produced noodles. Although it is interchangeable with regular egg noodles, the main differences are that kluski noodles are denser, have a more developed flavor, and are more resistant to fraying or breaking when mixed with other ingredients.

If your local grocery does not carry kluski noodles, you can ask the manager to order them, or you can purchase them online at many specialty foods e-tailers.