Saving music from mac to ICloud for play on Iphone

I have a mac book pro that I got summer 2010. I also have an Iphone and an Ipad. I have Icloud on my iphone and my ipad and i think on my macbook too. (or if I don't how do I get it?)

My iphone is only 16 gb and it is full it wont let me put anything else onto it.

Isn't there a way I can access my music from my Iphone to either my computer or my Ipad and it doesnt actually store it in my phone memory?!

Help please!

Thanks!!!