Also in the Zinn books, everything is always “Level 1”, “Level 2” or “Level 3”.
The “Level 1” stuff might just take an allen wrench and phillips head.
The “Level 3” usually involves specialized tools.
You can use it for adjusting your brakes, or a complete headset overhaul.
It’s not ALWAYS easy to follow, but something like that never is out of a book.
Here is a good place online for questions
http://forums.bicycling.com/forum.jspa?forumID=2
(warning: there are pricks there who will give people shit. Try to have a well-defined question, not just “there are suspicious sounds coming from the gears.”)
That could mean anything.
Is is your rear cassette (the set of cogs in the back?)
Is it your front derailleur?
Is it your rear derailleur?
Is is coming from your gear-shift levers?
Just to try to trouble-shoot, a common problem is your chain might be rubbing on the front derailleur (the little rectangle thing the chain goes through when it exits the front ring). Make sure you’re not in the big ring in the front and little ring in the rear, or vice-versa. THat’s called “cross chaining” and it’s just your chain rubbing on your derailleur from going front-to-rear at too sharp an angle.
If you’re not, then you need to turn the adjustment screws on your derailler. There’s too many ways the adjustment might have to be made for me to try to describe it to you here.