I heard the BeechCraft 1900D has no autopilot..or nav?..or something like that...can someone tell me then how the pilot fly's the aircraft I mean I guess there has to be some sort of autopilot...but haw would you fly the nav. profile?....I know this question seems distorted but i don't know how to word it

It has an autopilot allright. (actually it's a dual installation)
The panel is a little similar to the Super King Air we find in FS.
The autopilot/flight director system and "FMS" is made by industry leading Rockwell Collins which basicly provides all avionics for the Beech's, business jets, CRJ's and other RJ's....

With those avioncis you can fly as flawless as the b737...BUT, as you see I put the FMS in quotation marks above and that's a reason for it. Although the Beech 1900 probably has a Vertical navigation computer installed, you have to remember that a vnav computer knows virtually NOTHING about the performance of the airplane. A true FMS does.
An FMS can give you the most efficient climb rate, or if any given angle will result in fastest climb rate etc.

A basic vnav computer cannot tell weither a climb or descent at a certain point is advisable or not (ie too far away from dest. airport)

But like Crag said, it's not necessary to have all those fancy avionics, pilots flies the airplane just fine without it, but it will require more attention from the crew which can be tiresome in the long run

OTTOL can give us more info about this (may even corrrect me on the Beech, since I'm not 100% sure) hopefully he spots this thread