It has been 3 days now... the only thing that has changed at my end is I'm using a different ISP for my net access.
Now, I've done the following:
1) Contacted the site's administrator (it is a forum btw), and he has rebooted their DNS server.
2) Added the domain to my hosts file.
3) Followed all the suggestions here:
4) Followed the tutorial on this site.
And still I'm not able to access the site in question... so does anyone have any more suggestions?