Hello and welcome to the Seed commuinity Emine
I guess you've seen our own Seed RP setting (Seed the Second Chance) amongst the subforums here? We also miss Seed a lot, and so started an alternative text-only RP based on it. Maybe you can find some inspiration there.
Also, in the 'Data Fragments', there's a lot of stuff as you probably noticed, including the Seed repository (which is currently moving, dunno if Rookiedoo has set it up yet), that has most of what we have managed to save, although a lot, especially stories and articles made in the Seed setting is not there (yet).
Anyway, I know exactly what you mean, Seed was fantastic, almost a life-changing experience, certainly the best MMOG I've played, real roleplaying and all. Sooner or later something that is somewhat alike might pop up, and maybe someone will manage to get the IP released. Best thing might be to just cherish what was though, as it won't be exactly like that again. The IP is currently resting with the investors of Runestone, who lost their money when it crashed. It might be gathering dust, but I still think they'll want a sizeable sum for it. To my knowledge, no one has really inquired (and told us about it).
Anyway, hope you'll have a good time amongst us