In AutoZone at the nuts and bolts section, orange boxes, they're white clips for GM vehicles, $2.99 a pack.
As far as the bolts, they're torx heads and if you look under the inside door pull you'll see two cosmetic plugs. Remove those and you'll have access to the bolts, they're installed at an upwards angle. After that, just start pulling. Be mindful of the plugs for the window switches and courtesy light (you can remove it before hand, your choice) and door handle.