Um, you make bricks through the use of blockland brick files, or BLBs.
I'm not exactly sure how it works, but it's a text file where you have to literally set down the point in the 3D space for each vertice, define what sides show and don't show when covered by bricks, etc.
Ask soba about it, he'll help you or go to mod discussion and check out the blb reference at the top of the page.