Looks like you are having trouble with more than the postgres driver. Are you sure that the drivers are in /home/aolserver/aoslerver3_0/bin directory, because that is where it is looking for them. If not, then you will have to change your config file to point the the directory where the drivers are (on mine they are /home/aolserver/bin). Make sure that the drivers are in there. In the make install, it should install the driver in the directory that is specified in the Makefile.
Also, if you are just starting out, then I would recommend going to AOLServer 3.2 instead of 3.0.
--brett
