http://www.pinkpt.com/subguide.htm
There's an insane stack of guides for making neopoints on that page. a good numer are based on owning games, so it might not be too too helpful for you. i recommend the stock market, if you have patience.
just buy 1000 shares of some stock when it costs 15 neopoints per share, and do this every day, chaing stock often when you have to. then sell it when it hits 40-60 neopoints per share, depending on how patient you are, and you'll get a lot of money. it does take a fairly long time to get a profit though, so if you lack patience, this probably isn't for you