I think we've likely discussed this over email before (and if it was someone else I apologize), but I really don't know why this happens to you. Yes, 3000 players will run more slowly than 30 or 300, but in my testing 3000 players was not remotely unusable or even annoying.
Even if i add a new player to the database it takes terrible long time between typing and writing. i have to wait after every single letter.
This sounds to me like something else is happening, but I don't know what.
Have you tried using a blank database and adding a player? Do you see the same issue? This is easy to test without losing anything. Try this:
Select the Preferences tab. Then press the Data Stores button. Then press the New button. This will open the "Add New Data Store" dialog. Press the Browse button and browse to some known location (wherever you want to create a folder) and press the "Make New Folder" button. Give the new folder a name, and then press the OK button. You should now be back at the "Add New Data Store" dialog with the Folder and Name fields completed. Press the OK button. Next you should be prompted to initialize the new data store. Press the Yes button. Now you should be back on the Data Stores dialog, and your new Data Store should have been added. Right-click on the new Data Store and select "Make Active". Confirm it by pressing the Yes button. Finally, press the OK button on the Data Stores dialog to make the switch to the new, empty data store. At this point, you should exit the TD and start it again. That will clear out any cached players from memory. Now you're running with an empty database. You can confirm this by selecting the Database tab. Try adding a new player. Do you get the same issue (slow typing)?
To go back to your 3000 player database, select the Preferences tab, press the Data Stores button, right-click on your previous Data Store (should be the Default at the top) and select Make Active, then press OK.