info in the mainpage

Well... i've made a search on this forum and i think that i couldn't find what i want so.. i was wondering if you guys could help me out here. (i dont understand nothing in php)

What i really want is to put in this mainpage ( http://www.thefingertips.com/ )
info like number of users present in the forum / posts / members.
just this.
i know it can be done... but i dont understand anything of PHP.