So I just bought Thief 2 on GoG and I was wondering if anyone of you guys had mods that you use to make the game look better like widescreen and HD texture packs.

There's an unofficial patch that makes the game play on a much improved engine, at any resolution, with 8x anti aliasing applied. It's included in this: http://www.ttlg.com/forums/showthread.php?t=131106

Not sure about texture mods. I think there's some, but nothing huge.

Also, http://www.thief2x.com/ is the best mod ever made, for any game