Welcome aboard.
What kind of department you with? How much exposure have you had to this field?
First off, a very important question to ask yourself is do you want to be a Rescue Diver or a PSD? They are not related.
See what your target team requires, hopefully it's more than sport certifications once you’re onboard. Is it a Recovery Team or a Rescue/Recovery Team? To be a strong Rescue Team you need take home vehicles with your gear set up 24-7-365.
Then don't start putting a lot of weight and time into sport classes as they are contradictory as to what PSD training is about. Not back up this and that but more towards the KISS system and becoming self sufficient.
Go through the PSD site and read as much as you can as everyone had made some very good contributions. AND, don’t get excited when we don’t agree with each other. Just like everything else we have our disagreements, work through them and move on to the next topic.
Hold off on equipment until you know what’s going on. A Rescue Team should all have uniform gear where a Recovery Team can have more of a mix. But the more uniform the better. Then think trucks for gear and not sports cars. Trucks are for working and sports cars are for playing.
You might want to start out getting this book and reading it from cover to cover. It’s a good start.
http://www.bestpub.com/bookdetail.asp?BookID=1058&Category=Search/Rescue/Recovery
There is a correspondence course you can take but you need to be a team member first.
Good luck and keep asking questions.
Gary D.