hmmm do you mean an actual pattern to make pants out of?
because i know you can get that at most fabric stores. its like... a couple dollars, and you can use the pattern as much as you want.
I'd love to make my own clothes but the thing is I don't know HOW. Ha, but I bought a tye dye kit the other day from Wal*Mart so soon enough I'll be tye dying my own t-shirts!!
There are patterns at Spotlight. They have heaps of fabrics and stuff. Used to go in there all the time with my ex-wife and get stuff so she could make pants and shirts for our son.
if you want skinny jeans, i find its easier to turn them inside out, saftey pin them to the desired style (i usually go inside the legs, it makes it easier to walk in) and sew a new seam. if youre doing it by hand, make sure you sew the sitiches really close together or else they easily rip