Best way to get into Cambridge?

[Michael in Philly]

I'm going to Boston next week, for the first time in too long.  I want to spend several hours in the Harvard Square area (Thursday afternoon) and could well end up buying pounds of books.  In the past, I'd drive to the Alewife station, park at that garage, and take the Red Line in.  I'm staying in North Attleboro (barely Boston, I know) - is that what makes the most sense?  Or a train from there into South Station (bearing in mind the pounds of books), or drive to Cambridge and park?

Normally, I'd think the drive-to-Alewife-and-take-the-T option would be a no-brainer, but wouldn't mind driving, if only for the fun of driving and particularly seeing the new 93.  Is parking so expensive or traffic so bad in Cambridge that just driving up 95 and 93 to - is it Storrow Drive? - is stupid?  (Obviously, I'd wait until after the rush hour to try to drive back to almost-Providence.)

Thoughts?  Thanks.

[citrus]

If you're coming from North Attleboro, consider driving to Braintree or Quincy and taking the Red Line from that end.

[Michael in Philly]

Not a moment too soon, it turns out!

http://www.boston.com/yourtown/news/cambridge/2011/06/the_globe_corner_store_closing.html?comments=all

Wow.  Map-lovers take note....

[Alps]

You can definitely park near Harvard Square, you just have to be patient. Helps to know the streets, too. Most of them are restricted to residents with permits, so it takes some hunting.

[InterstateNG]

When I visited Harvard, I just parked on the street near the stadium.  Not the greatest idea if you're buying books.

[Michael in Philly]

Especially since they're forecasting the same 95 degrees there as here.  (I keep checking, hoping it'll change.  I love summer, but that's excessive.)
I'll probably just spring for a garage - keep the car out of the sun while I shop.
Thanks, all.