Basically, just use some of the same coding you used in your header.php file in your vbulletin header file, after you have the header looking the same, its just a matter of having the same exact colors in vbulletin as you do in oscommerence.
I still have a lot more work to do, I still have to integrate my footer of oscommerence and vbulletin.
All I need now is for someone to integrate the databases so vbulletins who's online will show users on the main site, too!