welcome here!!
and your trackmania sound site is one of my ideal too

I have start last year here for the textures I us to make my mods and sounds i have from games extractions (use or not yet use in RPG ).
So I have a lot of sounds (im in music industry-so big sound fx banks to give) that i could share with you!
PM me if I can help ^^
MY REMAKE TO CHANGE "pulp", THE ORIGINAL INGAME MUSIC :
LISTEN PULP REMIX HERE