Second/third level nav

10 points to whoever can point me in the right direction. About to code up a header but want to know the best way of going about it. Here’s the design:

http://d.pr/JMZk

1. I can do this w/ wp_nav_menu and superfish. pretty straightforward.

2. Need to accomplish breadcrumbs directly in the theme(no plugins). Again, shouldn’t be too hard: http://dev7studios.com/resources/roll-your-own-breadcrumbs-in-wordpress/

3. Here’s where I’m lost. Not sure how to grab sibling menu items to display as tabs. Also, need a some type of conditional to handle if there are no siblings(then display no tabs)

Just looking for a push in the right direction. Thanks!