PASSWORDS
For a good intro to password use,
go here
Below are some free programs that will store your passwords securely on your computer.
They only require that you remember a single password to access the storage.
They will also generate a good password for you if you don't know what to use.
KeePass:
Download here
Password Safe:
Download here
Roboform:
Download here
The free version of Roboform is limited in the number of passwords it will store. I think 10.