Originally posted by: sswingle
To expand on what others have said, go into the Playstation store, go to the Add On section, choose rock band, and amonst the songs there will be a song export key for 4.99. Buy this and download it. Then put in the rock band 1 disc, and in the game under Extras, there will be an export option.
As far as other songs, buying them in the store is how I always go. There are a handful of songs that are free, and a handful priced at 99 cents, but most are 1.99. Also look for packs, as a 4 song pack will usually cost something like 6.50 as opposed to 8.00
Also, there is a code on the back of the rock band 2 book that you can go online and register, they give you yet another code, and you can put that code into the store for 20 additional free downloaded songs (no, you can't pick which ones)