There is a free version of Live to try out, but it's limited. I'd say the easiest one to use is Garage Band, but you need an Apple PC for that, or an iPad. If you have an iPad, there are some pretty nice DAWs available, like NanoStudio 2, Tabletop and Garage Band—all of them are easy to use and cheap to buy. As for the PC, I'd say that FL Studio is probably the easiest to use, but it's not free, coming in at $200-300 dollars depending on which version you buy. The cheapest DAW is the open source Reaper, which is $60 for a license.
There are plenty of options out there, it's just a matter of what you want.