Yeah, the shemagh is one piece of head gear that you won't regret buying. I personally use a shemagh, ESS Profiles, and either a helmet or hat every time. I even use my shemagh when I go snowboarding.
Shirts tied around your head also work fairly well if you're wearing a helmet.
You definetly want to go with some ANSI z87.1+ rated eyewear. ESS makes some really solid pieces, several of which are available at the Allied Surplus on Northern (they're only about $20 used). Arena Flak-Jaks are also great goggles, as they were designed to fit the MICH style helmets. However the Flak-Jaks are bulkier than ESS Profiles.
You may also want to look into a paintball or airsoft mask, because, as stated above, some places require minors to use them.
Oh, and to add about the fogging issues: you won't have too much trouble if you have it wrapped right (even if it is around your entire head). It may be a bit of a problem if you are going for a sniper role or if you don't move very frequently, as the lack of airflow will cause them to fog.