You should find an add-on called new tab button on right (or something like that) install it, restart firefox and you'll have a new tab button just to the right of the last tab opened (just like in IE)
That was a rubbish answer, sorry. Control and T will certainly open a new tab, but you can set it to open a new tab from links and from your search box.
Tools - options - tabs
Make sure 'new pages should open in new tabs' is ticked