"If I could find someone with a hacksaw"
I don't remember which store this was, but I purchased a simple hacksaw blade with a basic handle attached. That's all there was to it, and it was cheap.
If you get more advanced, you buy a Dremel tool. That is a small electric tool that will accept all sorts of drill bits and cutting blades. In fact, there is a cheap Chinese knockoff Dremel tool on the market for about $10. Ask around your neighborhood, and somebody will have a Dremel tool. In fact, the Dremel tool owner will likely cut your aluminum for you to prevent a beginner's accident.