[sdiy] 16x4 sequencer with add-on modules thought

[bill bigrig]

Howdy,

 i have an idea for a 16x3, or 16x4 sequencer that would be a 'master unit' with add-on modules to increase the steps in increments of 16. Or just the main module with identical add-ons that can be added for expansion of steps, or separate sequencers running in tandem. My question is, where or who can I take a circuit drawing and have a PCB designed for it? It can be sold as a complete unit or in kit form. The main thing is, it can be cascaded to allow multiplesof 16,(+/- sreps in the final stage) to acheive long sequences if the musician so desires. Any PCB design resouces out there?
Rig