Here are a few of the online sources I use.
Course texts Human Bio
I would also like you to check out a few newspapers/journals for up to date stories.
Here are a couple I like:
The Guardian (The European newspaper of the year)
Any articles you may want from the Times that they want money for can be obtained free of charge through the University's expansive online databases. This is also true for most of the popular science journals (Scientific American, Discover etc)