As Nick says, I believe that most C-41 kits are in liquid form, although there may be some exceptions. Paterson sells separate developer and bleach/fix items that, when bought together, could be considered a "kit." (B&H has such a bundle, but I believe their bundle price is higher than the individual components, so check on that.) Whatever you buy, if it lacks a stabilizer, you might want to look into getting some separately to ensure your negatives won't fade prematurely. The stabilizer contains formaldehyde, though, so be sure to wear gloves when using it. (Note that non-formaldehyde "final rinse" isn't the same thing as stabilizer and doesn't provide the same benefits.)