First and foremost, go to AMD and Intel and ask for sponsorship from them and tell them you are setting up Internet cafe and PC buying advice center. And by getting their sponsorship, you will be increasing awareness in the locality.
Make you internet cafe a cafe and buying advice center so that people can come to you and ask for buying tips, which h/w to buy etc.
Just my two cents.
PS: Most of the guys/gals who come to internet cafe will not have a PC at that time and will be buying one in future.
AMD config:
Sempron LE 1250 : 1.5k
ASUS M2A MX: 2.3k
Intel config:
Intel Celeron 430: 1.9k
or
Intel E2180 dual core : 3k
Gigabyte GA-G31M-S2L : 2.4k
Rest of the config:
Transcend 1Gb DDR2 800MHz: 850
Seagate SATA2 80 GB: 1500-1700
samsung/sony dvd burner
BenQ 15 '' T52W LCD : 4.5k
cabinet+SMPS : your wish
Logitech m/m k/b+mouse: 700