I find that I don't use a whole lot of 12x12 paper, so until I change that, I have put myself on a "don't buy it unless it's for a specific project" restriction.
But that doesn't mean that I don't have some on hand already. Back about a year ago I did the organizing class webinar with Tiffany Spaulding at Scraprack. While the Scraprack doesn't fit for my style of scrapbooking, some of the purge and organize plans did. I had a few sets of the 12x12 Sterilite drawer units and I sorted my paper by her suggestions.
*Plain and monochromatic paper goes in drawers by color.
*I have one drawer of specialty papers, two drawers of multicolor (stripes and plaids, and floral) and several drawers of paper by theme (seasons, holidays, baby, etc). I put the themed papers in large baggies, labeled for theme, and put the baggies in the drawers.
*Since my scrapbooking is done in Stacy Julian's Library of Memories style, I also have a few of those snap envelopes that have coordinating papers for special albums, like my Christmas album.
You can see the drawers in the attached picture.
Quiltzi...High Plains Member of PunchkateerzI'll stand with arms high and heart abandoned,
in awe of the One who gave it all.
I'll stand, my soul, Lord, to You surrendered,
all I am is Yours.