Garmin E trex is fine. The kill switch can be found at REX < CP Performance etc. The drivers  raise their hands to acknowledge the crowd on the Parade Lap. They will also raise their hand if they break down to inform other drivers. Don't worry about making mistakes. Everyone who has raced has made some and thats how we learn.Its all about being safe and having fun.

What are you guys using for:
GPS, will a garmin etrex work?
Kill switch?

also what are the rules as far as driving out there. obviously theres a parade lap, then I see some guys raising their hand occasionally. Is that for motor trouble or what???  I admit I am new, just trying to learn this stuff so I dont do something stupid out there.

A mercury style kill switch is what you need. Only two types, magneto and reg ign. Driving rules should be reviewed in your APBA handbook in the inboard section. A few rules off the top of my head are:
1. Maintain your lane through the first turn.
2.No cutting the track unless its to line up for the start or there is a black flag.
3. one must be atleast 4 boat lengths ahead before lane changing in front of another boat.
4. know your flags
5. acknowledge the flag man and napolean on the parade lap.
6. PAY ATTENTION TO THE FLAGS, somebody may have had an incident on the course and the flags will let you know.
7. Stop IMMEDIATELY if you see a flare.
8. always listen to terry and if you have questions, ask him.