Electronic Product Enclosure Design

I am developing couple of electronic products , small , medium , large size , need a mechanical enclosure designer who has good experience in this field.

I need some one who has experience with electronic product packaging , enclosure design , conversant with type of front panel components normally used in such products( switches, knobs, displays, connectors, card guide etc). Proto models will be made in metallic enclosures , once satisfied , plastic enclosures have to be designed.