./bin/nsd -t openacs.tcl

I get following error in log file:
**********************************************************************

[27/Feb/2001:20:09:53][2635.2051][-sched-] Error: dns: gethostbyname
failed: temporary error - try again

[27/Feb/2001:20:09:53][2635.2051][-sched-] Error: urlopen: failed to
connect
to 'http://info.webcrawler.com/mak/projects/robots/active/all.txt': 'R
esource tempo rarily unavailable'

[27/Feb/2001:20:09:53][2635.2051][-sched-] Error: dns: gethostbyname
failed: temporary error - try again

[27/Feb/2001:20:09:53][2635.2051][-sched-] Error: failed sending
email note to somenerd@yourdomain.com

[27/Feb/2001:20:09:54][2635.2051][-sched-] Error: Ns_PgExec: result
status: 7 message: ERROR:  content_sections: Table does not exist.

[27/Feb/2001:20:09:54][2635.2051][-sched-] Error: dbinit: error
(localhost::openacs,ERROR:  content_sections: Table does not exist.
): 'select section_url_stub
    from content_sections
    where scope='public'
    and requires_registration_p = 't''

[27/Feb/2001:20:09:54][2635.2051][-sched-] Error: Database
operation "select" failed (exception NSDB, "Query was not a statement
returning rows.") Database operation "select" failed (exception
NSDB, "Query was not a statement returning rows.")
    while executing
"ns_db select $db "
    select section_url_stub
    from content_sections
    where scope='public'
    and requires_registration_p = 't'""
    (procedure "ad_filter_restricted_content_sections" line 4)
    invoked from within
"ad_filter_restricted_content_sections"
    ("eval" body line 1)
    invoked from within
"eval [concat [list $proc] $args]"
    (procedure "ad_run_scheduled_proc" line 43)
    invoked from within
"ad_run_scheduled_proc {f t 5 ad_filter_restricted_content_sections
{} 983284789
0 t}"

[27/Feb/2001:20:09:59][2635.2051][-sched-] Error: Ns_PgExec: result
status: 7 message: ERROR:  spam_history: Table does not exist.

[27/Feb/2001:20:09:59][2635.2051][-sched-] Error: dbinit: error
(localhost::openacs,ERROR:  spam_history: Table does not exist.
): 'select * from spam_history where status = 'sending''

[27/Feb/2001:20:09:59][2635.2051][-sched-] Error: Database
operation "select" failed (exception NSDB, "Query was not a statement
returning rows.")Database operation "select" failed (exception
NSDB, "Query was not a statement returning rows.")
    while executing
"ns_db select $db "select * from spam_history where status
= 'sending'""
    (procedure "flag_interrupted_spams" line 3)
    invoked from within
"flag_interrupted_spams"
    ("eval" body line 1)
    invoked from within
"eval [concat [list $proc] $args]"
    (procedure "ad_run_scheduled_proc" line 43)
    invoked from within
"ad_run_scheduled_proc {f t 10 flag_interrupted_spams {} 983284789 0
t}"

**********************************************************************

When I try to visit http://localhost:8080, Netscape give an error box
saying "Document contain no data try again or contact the server
admin"

Also AOL_HOME/bin has postgres.so file. Also the datamodel was loaded
without any error.

Thanks

I would try to fix the DNS first. Be sure that the following things work:
ping localhost
ping 127.0.0.1
nslookup localhost
nslookup 127.0.0.1


I am not sure, but I think it that not having a correct DNS might mess up contact between AOLServer and postgres. Furthermore, from the sample above I guess that you named your database 'openacs', if so your ns/db/pool/main section should look like this:

ns_section "ns/db/pool/main" 
    ns_param Driver postgres 
    ns_param Connections 5                  
    ns_param DataSource localhost::openacs 
    ns_param User nsadmin                   
#    ns_param Password "" ;# using internal-auth 
    ns_param Verbose Off                    
    ns_param LogSQLErrors On 
    ns_param ExtendedTableInfo On 

Ryan suggested checking if your datamodel was loaded correctly, but this test may be a bit more informative. And yes, please do check your datamodel.txt file.
su - nsadmin
psql openacs -c "dt"
You should see a list like this:

               List of relations
              Name              | Type  |  Owner  
--------------------------------+-------+---------
 acs_modules                    | table | nsadmin
 ad_categories                  | table | nsadmin
 ad_domains                     | table | nsadmin
 ad_integrity_checks            | table | nsadmin
 (...)
--More--

If you didn't generate a datamodel.txt file and the tables aren't there, please just:
su - nsadmin
dropdb openacs
And redo from 'creating the database and loading the datamodel' in the manual, and check for errors in datamodel.txt if it still doesn't work.

Hope this gets you anywhere.