Brand new to the "fest"

Hello all, my name is sam. I am living in portland oregon. I own a 1988 E 528. It seems to run alright. Its got 180k on the odomoter but it still gets around 30+MPG on the highway... bout 20+ in traffic... so far... i like it very much
I am having some questions about the stereo set up for these cars. I already got my code and my radio head unit (stock) is on but i am not getting any sound. I belive there is supposed to be a factory amplifier somewhere? I belive it got removed, but i just don't know... i also can bearly hear some noise or music when its playing under my center console... (right above the ash tray) Any info? let me know heavy_sam@hotmail.com I just want tunes man.. !