The best place is probably Bricklink.
The best place to buy cheap Lego is from the Internet. Sites like eBay and Amazon are the best, and most reliable for purchasing Lego sets, minifigures, parts etc (new and old).
You have to buy the "use old save" extra on Lego Star Wars: 2.
$77
you buy it at a Lego shop
The best place to buy old Lego sets are from the Internet. Sites like eBay or Amazon are among the cheapest, most reliable sites to buy Lego. I'm sure you'll find lots of Lego Spiderman sets there!
eBay, Amazon or the Lego website are the best places to buy Lego train sets.
No, you can only buy 'Catwoman' on the game.
If you bought the NXT legitamilty it should have come with a disk, if the software is out of date, you can download many patches and possibly even the entire software package at the related link.
Sadly Lego costumes do not exist, however you can buy weapons etc. from your nearest Lego store.
Buy it!!
You buy them