I'll apologize for my noobishness in advance.
Anyhow, I need a wireless remote controlled on/off switch (Radio frequency would be best I figured). I don't really need any specific mode, momentary would be great. I also need it to run around 4-6 volts DC and about 2-5 amps. I haven't been able to find one on Amazon or eBay or anywhere and so I figured I'd ask on here if anyone knows where I can get one or how to make one. A big thanks in advance!

 

I recently bought some of the 4 button 315MHz key FOB transmitters with matching receivers (the kind with the strappable address codes). It was trivial to add relay(s) to the output(s) of the decoder. With a full-size dipole antenna on the receiver, the reliable range is about 300 ft (100m).

I am using these to control a swing gate and two garage doors. Work much better than the ones that came with the garage doors...

 

I found something similar at a Walgreen's drug store. It was set up to remotely turn lamps on and off. You might check for something like that and adapt it to your needs.

 

Thanks all! I found remote similar to the one you posted, MikeML. That's probably the one I'll go with