Given the popularity of GarageBand and it's use as a musical notepad and entry level DAW, it comes as no surprise that other software developers have borrowed from that magic and incorporated some GagargeBand-ness into their own offerings, also long term, most of you will need something a little more professional once you realize the limitations of GarageBand itself.
With that in mind, here are some great alternatives to GarageBand for Windows which are designed for the PC from the ground up with varying levels of GarageBand-ness
Cutting to the chase, of all the DAW's listed here Mixcraft (By Acoustica) is almost law suit close to GarageBand. Acoustica's mantra is that software should be easy to use, an ideal with which I wholeheartedly agree with. If the tool is getting in the way of creativity and productively then it ceases to be a tool and becomes a hindrance.
If you've ever tried GarageBand then the recording and mixing layouts are almost identical.
But Mixcraft looks deceptively simple, in actual fact it has almost all of the functionality that you find in much more expensive DAW's like logic Pro or Pro Tools but at a fraction of the price. Through it's releases Acoustica have consistently added functionality and value to the point now at version 8 you'd be hard pressed to find something that it hasn't now got. There are several versions available including Studio and Pro with varying prices and features, mostly the difference is in the bundled VST instruments and plugins, the pro version, for example, comes with Ozone one of the industry standard mastering plugins and with all versions under $100 it's easy to see why Mixcraft has carved out an important niche in the DAW market.