A) please list some more details -- size, price range, quality, any preferences, etc.
B) the search function or even a quick scan of some stickies would more than answer your question
C) consider renaming the title of this thread to something more descriptive, such as "Need advice where to purchase a 400mW Green Laser".
D) If you have a decent sum of money and you want to get something of proven and significant quality, but yet at a spectacular price (well for that level of quality) then check out Glenn's CNI GB's in the 'Group Buy' section. They take a while to complete, but if this isn't a need-one-now-or-i'll-die situation then I'd consider an investment of that type. Look around for GB#8, which is starting soon (GB#7, the last one, has just recently closed).
Thank you everyone, I might get one through the GB #7.
Also I have seen this website Top Laser Pointer - Green Pointers the lasers are from CNI, the people are really nice. What do you think about the lasers? Are they the same if I buy them from another site?
if it's ur first green laser, i recommend this 350-400mw one at █▓█350mW - 400mW Green Laser Pointer Pioneer Series,$779.89,Freak Lasers. The peak power can reach 410mw, little ir residual, and more importantly, they offer a year's guarantee and u can return it for refund whenever u're dissatified. They will pay the UPS or DHL shipping fee for u. Good enough. They also guarantee its made of the 2.5w n-light 808nm, c-mount. Anyone can test it.