Need A Routine.. Any 1 Help?

Ok so im 14, and pretty skinny for my age (arms and body). So I wanted to start a workout routine to get my arms bigger and to get abs. The problem is, I dont really got any equipment besides dumbbells. So I need a routine containing mainly pushups, sit-ups, dumbbells, and any other workout without equipment. Also I wanna know what type of foods i should eat each day, I read a post on here http://www.discussbodybuilding.com/Master_Grocery_List_Stick__the_top/m_120408/tm.htm .. and dont really know which 1's i should eat...

So If someone could help me it would be really appreciated.

http://www.discussbodybuilding.com/m_111173/mpage_1/tm.htm

Read this, very valuable information.

Ask questions if you have any afterwards. :)

The post above is a very good one.

I started with the max-ot training system personally. If your intersted in it here's the link http://www.ast-ss.com/max-ot/max-ot_intro.asp they take you step by step week by week explaining pretty much everything. The site is beginner friendly.