The easiest way to go from CFS to IL2 is to make your IL2 keyboard controls match what you had in CFS.
That's what I did over 8 years ago.
Now with that said, and from experience.
If you have a Joystick that has a pro-filer, and are using it in CFS then leave the IL2 controls as stock as possible, and make the pro-filer manipulate the IL2 commands to resemble your CFS stuff.
Head sets, well depends on your location, and available stuff at your local retailers, unless you order Online.
I'm using a set of Platonic at the moment, they work well, but the mic boom has to be taped into position to hold still.
I got three years out of an EDimensional set. and before that just some cheap 20 dollar logitecs worked well, but kids were too rough on them, back then. Kids are gone, and off to college, so I could probably get by cheap again.
Dang it Zooly, you got me Pining for a new pair now.
http://www.newegg.com/Product/Product.aspx?Item=N82E16826158082
http://www.newegg.com/Product/Product.aspx?Item=N82E16826158075
http://www.newegg.com/Product/Product.aspx?Item=N82E16826158069