Any idea of how much lower you want to go? Typical 'low' springs are generally 25-35mm lower than standard. You can also get 'Superlow' springs which are generally 45-50mm lower than standard. Kings also do an Ultralow spring which is getting closer to 70mm lower than standard.
Just remember, with short springs (depending on how low you go), you may need short stroke struts/shocks to match. This ensures that the springs remain 'trapped' at full suspension drop and that you still have suspension travel rather than hitting the bumpstops all the time.