Hello.
Personally, I am a BIG fan of simple, clean websites. Your site is very easy to navigate but it is too white.
If you add a dotted outline around the left nav, it would look a bit nicer. And as Rick states, you may want to add a brief paragraph stating the obvious (ex. Welcome to our site. We offer free classifieds... and so on). I see that you have added a welcome line but maybe you can add a little more wording and make it a short paragraph.
Regards,
Zeeshan M.