@Peter Hansen, welcome. I am currently military living overseas. I have one house and am working on closing on number two (which I purchased on Auction.com), so also a beginner.
Some humble advice:
1)Spend your time deployed learning. There are so many resources on BP for free you can use your entire time (365/180...whatever) learning for free. I recommend the podcasts, the beginners guide, and if you want to pay, the low/no money down book is a good start.
2) Start looking now, but when you get back find your team...at a minimum you'll need a property manager and a realtor. Both should be familiar with working with investors and military members who won't be around all the time. Start with recommendations (on here is a great place to get them), and then interview them...remember, they are working for you!
3)Take a little bit of time every day looking at properties on line. Also, after you get some recommendations on realtors, you can start that conversation via e-mail. It's very easy for them to add you to their list and send deals from the MLS automatically.
4) I'm a little out of my depth here, but my decision has been to hold off on my license because I'm not 100% sure where I'm going to settle. Unlike some professional licenses, the realtor license does not transfer state to state. ...I plan to do it sometime in the future, but right now it seems like a bit of a waste.
Hit me up with a PM if you want to chat...and use the deployment wisely.
Steve Marshall
Bangkok