Well, we certainly could compile a stock of these sorts of elements, but honestly, they're so easy to make that it seems sort of pointless. Photoshop has specific tools just to make elongated ovals and arrows in one or two clicks.
Download one of the trials of photoshop and mess around with it. You'll pick stuff up FAST, trust me. I taught myself photoshop and illustrator, and if I can learn it, anyone can.