1. I know of one,
http://www.averyspecialcollection.com/
You could also do a Google search for "miniature quilt patterns".
2. Not that I know of, other than make sure your seam allowances are accurate if you reduce using a photocopier.
Sometimes, depending on the quilt, I'll use a 1/8" seam instead of a 1/4" seam allowance, or often times I'll trim the seam allowance to 1/8" after sewing.
I also usually paper-piece minis, since it's very accurate.