What hardware needed to to run asterisk?

hi,
am planning to develop a embedded asterisk IP-PBX, with 4 Fx analog ports(2FXO+2FXS),on BF537-Stamp, uClinux (blackfin/uClinux)
so i builded a uImage (from atfin).
along with BF537-Stamp, what other hardware i needed. and where can i get.

any sugessions please…

Regards
Chandu