Check out some of the other 'new player' posts. Just leveled up a coercer myself and had a blast doing it, its nice to have so much control. I don't have any real good 'coercer' suggestions but more stuff in general: Find and join a good guild, it will help a ton in convenience as you level. If you get stuck on where you should be at what level, google 'eq2 golden path'. EQ2.zam.com is a great resource for quest help. If you are just leveling up in outside zones, you won't need a mercenary, but if you decide to do dungeons without a group, you'll probably want AoD for that, they can be very helpful and allow you to do things and go places you couldn't solo. If you are on Permafrost, feel free to look me up sometime
Check out Classes Mages forums. You can find lots of useful advices for coercers there. http://forums.station.sony.com/eq2/index.php?forums/mages.21/