PSP memory card question?

I just bought a PSP and I don't know anything about the memory cards. Where can I get one cheap? I only need 1gb for now.

Can I use the same cards for digital cameras or do I need one specificaly designed for the PSP?  

What's wrong with a Sandisk memory card?ColonelWilks

You can get a 4 gig sandisk for $70 shipped at amazon now or a 1 gig for $23, 2 gig for $38.  I'd go with the 4 gig.  You can never have enough space!

http://amazon.com/s?url=search-alias%3Daps&field-keywords=memory+stick+duo&tag2=dealsdog-20