So I'm new to using Arduino and wanted to know can I set up a laser trip line that will then send a message to a printer to print out? So here is the whole project. We are having a going away party for our boss that loves golf, so our office is doing mini golf courses in the office. Our IT department wants the hole of our part to have a trip line so when you get it in you get a print out saying you finished the hole. Is this possible with an Arduino? Can I have run a program that when the line is broken the golfer gets a print out? Thanks for reading.
yes is probably possible.
if you provide more information the answer will be more exact 
- what laser do you use- datasheet
- what printer do you have in mind - datasheet
- sensors you think you need
- how much text do you want to print (memory is limited)
- ...
I would like to either use
Photoresistor GL5537 5537 LDR Photo Resistors with a laser pointer.
Or use Geeetech Infrared proximity switch module compatible with Arduino/Iduino if this can detect a ball moving past it.
http://www.amazon.com/Geeetech-Infrared-proximity-compatible-Arduino/dp/B00AMC1V2C/ref=pd_tcs_compl_p_71?ie=UTF8&refRID=17Q5RNDJGS5AHS3NA1YY
The printer will be like an HP photosmart all in one, because I have one here, or I could use a laser printer.
The golf hole is going to be help desk themed and we want it to print out something like "Thank you for contacting the help desk. You work order has been closed"
I hope this info helps
If the office where the hole is lighted, place the LDR in the bottom of the hole and the ball will cover it when putted in. Should cause enough change in resistance to detect. No need for a laser or other light source but the office lighting.
Any idea of how I hook a printer up to an Aruino? I want it to print off a page once the ball drops into the hole or breaks a laser.
I don't know how to talk to a modern printer (USB). I would look into printing using a Processing program that is triggered by a command over serial from the Arduino.
If you are in an office environment you might have wifi and networked printers? Maybe the Adafruit CC3000 shield Adafruit HUZZAH CC3000 WiFi Shield with Onboard Antenna : ID 1491 : $39.95 : Adafruit Industries, Unique & fun DIY electronics and kits might be useful?
I don't think Adafruit have a ready to run "network-printer library", but I think it could be handy for experimenters and someone on the forums can either tell us if it is a no-go, or alternatively may be able to help you implement it. Slightly out of my league 
Or maybe just driving a parallel port directly with the Arduino I/O pins? Most office sized lasers I have seen usually still have a parallel socket on the back of them (as well as their wifi and USB). No wires sounds more attractive to me.
Cheers, Rob
As other suggested, use a LDR that gets covered when the ball runs by.
Use a sketch on your Arduino that makes it emulate a keyboard, and make it send the keypress <CTRL+P> followed by and then connect this to an old laptop, connected to the printer via cable or wifi, with a document or image, showing what you want printed on the page.
// Per.
How about sending a serial line to a computer that runs a simple C# program?
Your IT department would certainly need to be able to figure that out right?