Wow! That is honestly the best "getting into airsoft" text iv read. Anyhow about some questions you have, id like to share my 2 cents on them. Im an active airsofter for almost 2 years now and trust me its the best sport/hobby/lifestyle anyone can have. Its great exercise and great meeting people and interacting with your friends. The question about what gun you should get, what variable of this and that, what gear and so on, its all on personal preference. Some people like ACU's some people still run DPM others run Multicam and so on. The variations of things you can buy for airsoft are endless. As for what gun id recommend an M4 in the beginning simply because there are hundreds of variants plus they are the most common types of airsoft guns out there. You can find spare parts from anywhere for M4s. On mil-sim and WW2 re-enactment id say give it a shot once your all set up with your gear and a bit more experienced. Youd enjoy it more in my opinion. Mil-sim is too hard core for the average airsofter and it might give you a wrong opinion on what airsoft is. As for how to start and where just get AV'ed (what im going to do as soon as i come to Canada) and start from there. Get yourself a good pair of ballistic rated glasses and show up at a game one day. Im pretty sure people in Canada rent or lend airsoft guns for newbies and see how it goes from there. It might look good on youtube and ASC forums but you might not like it due to many reasons. Anyhow thats my opinions on the subject. If you need any questions answered or whatever else airsoft related just hit me a PM. Id be glad to help with whatever is needed.
P.S Airsoft is a drug. It gets through your system and never lets go. You think about airsoft 24/7.