Dear sirs, i have 2 questions regarding visa to Hong Kong

1- if i do not have invitation from HK , but i have contacts their and i wish to make a business trip, would you give me one, i can present i letter of recommendation from the chamber of commerce, my company is registered under first degree category.
2- do i have to attend myself to the Embassy, or can i send somebody on my behalf.
thanks for your kind cooperation
Mounir