Hussar, catsclaw,
Here are some answers.
There was no formal SRD until months after release. It might even have been nearly 9 months. (see below, it was longer--it was over a year)
We got draft rules from the PHB (which I still have, I spiral bound them) several months prior to launch. I would say maybe 4 months, at most. We got the MM a bit after that. Maybe 2 months before launch, at most. We barely had the DMG at all.
Last time we had the OGL listserve that we were all using daily and extensively. We were in constant contact with Ryan Dancey, the head of D&D and the head of the Open Gaming movement. He started the lists, which have (as of the other day) been closed down.
Prelaunch of 3E there were very few announced companies. Atlas and GreenRonin played things very close to the vest and released products at GenCon without a ton of pre-release hype. Necro had a web site up. Several other people had web sites up prior to release, most of which never really even materialized into real thriving companies. Fiend Games comes to mind.
At launch, there was very little available--GR's Freeport, Atlas' 3 Days to Kill and Necro's Wizard's Amulet (which has the honor of being the first d20 product available, as it was released electronically at 12:01 of the first day that was allowed for release; though GR and Atlas have the first commercial products that they sold that first day of the con). WW had the Creature Collection (that I produced) almost right away. It beat the official MM to release, which was quite an accomplishment.
Basically, the third party companies were different then. The general product was 32 page modules (other than the Creature Collection). And that is how things stayed for some time. Those products arent as viable today as they once were.
Buit back in the day we had pretty constant support and contact with Ryan Dancey. There was a real direct connection between the potential third party publishers and WotC.
We worked of a "gentleperson's agreement" that was in the form of an email on the OGL lists that was addressed "To Clark and anyone else wanting to make products for launch" and then it basically said what we could and couldnt use until the OGL and SRD were finalized.
Reviewing some older products, I notice that the OGL iteself had been finalized by the time we released Crucible of Freya, but the d20 STL was still a draft and there was not an SRD yet. Reviewing Demons and Devils, the same was true--the OGL was finalized but the s20 STL was still a draft and there was no SRD. By the time of Rappan Athuk 2 and Prisoners of the Maze, we were dealing with version 1.0 of both the OGL and the d20 STL and we had a draft of the SRD but it was not yet finalized. Same with Siege of Durgham's Folly (an adventure written for us by Mike Mearls back in his early freelancer days).
Here are some dates for you:
Crucible of Freya was late 2000. The OGL was done, but only a draft of the STL. No SRD yet.
Rappan Athuk 1 was late 2000 and only a draft of the STL, no SRD.
Demons and Devils was March of 2001 (for GAMA). As of that time still only a draft SRD
Rappan Athuk 2 was August of 2001 (GenCon). Still only a draft SRD.
Prisoners of the Maze was September of 2001 (just after GenCon). Still only a draft SRD.
So that means it was well over a year before a formal SRD was released. Let alone when it might have been posted online for people to view.
Hope that helps put things in perspective. There wasnt even anything close to a publically available SRD for over a year after launch of 3E.
Clark