You buy one, and connect it to the psp.
buy one
yes (if where you bought it from gives you one or you can buy one when you buy your psp) or ask
the core psp system from wal mart only comes with the console. however, sometimes you can buy the following....a starwars collectors edt. that comes with the starwares game, a daxter psp that has family guy movie, daxter game and a 1 gig sony memory card, or the plain one that comes with nothing other than the system and the battery pack.
you can buy a cheap one at gamestop
You go to Sony or any store and buy the disk. Or you can use the PS3(if you have one) and buy it there and get it to your PSP by USB drive. Or you can directly buy it off the PlayStation Store in your PSP.
You cannot play with multiplayers on a PSP with just one PSP system. You can play with multiplayers with a PS2 gaming system.
You don't have to buy the 3000, you can just buy the 1000 or 2000 and update the system to modern. I found my old PSP and its the 1000 one and i couldn't play birth by sleep without updating my system. Updating free too.
buy a new one
buy new one
Try ebay.com There might be a used one on there, and they usually come with games and stuff if your lucky.
One can purchase a memory card for the PSP from numerous stores and online retailers. One can buy them from Best Buy, Target, Walmart, eBay and Amazon.