Start with pg 6 of the PHB.
Note the section on "Attack Bonuses" it will lead you where you need to go.
Basically weapons don't have attack bonuses, properties of weapons do (like magical enhancement or masterwork quality).
Also try the index - it is actually fairly good in the PHB.
Do not, repeat do not attempt to learn how to play the game using only the SRD - there are far too many things a new player needs to know that are contained only in the PHB. Illustrations are a prime example.
