I may be over complicating my project, but I have a simple reed switch, and if I could have it wirelessly tell my Arduino that it is closed, it would save me some wiring. What would be the simplest, and cheapest way to handle this?
You can you use rf module 433mhz with encoder decoder ic. check this link to make a rf module.
http://embeddedsystem1.blogspot.in/search/label/decoder
In transmitter side replace the switch with your reed switch so that when the reed switch get active it will send a signal to receiver.
In receiver side replace the led with your arduino digital pin so that when you get signal from transmitter it will be detected on arduino digital pin (high,low).