Probably wouldn't be difficult, although I'd recommend against a 5-7w laser for your first build. It's just too powerful. My first was a 1W 520nm green and even that's almost too scary, especially given that a "true" 1W green is unheard of in that "gatling laser" market. You have to use an expensive diode that they just won't be willing to use and then charge $40 for. Like others said check out the sticky threads, there are many different sources for parts to begin your build. One I will recommend is DTR's website for sourcing diodes, modules, lenses, and drivers.