Stich Witch. It's a tape-like stuff. Looks kinda like Teflon tape. Basically, you put some snips of the stuff between what you want "sewn" together, and steam-iron it. The stuff melts into a cloth super glue. Warning, it is permanent! Make sure you have your folds just right where you want them before you iron. Measure twice, cut once.
That's the permanent solution. A quick fix is Elmer's glue. Same concept, fold where you want the crease, use Elmer's (or just about any art-and-craft glue stick stuff), let it dry, and you're good till you wash it.
But needle-and-thread isn't that hard to master. Just use thread as close to the same color as the pants, and use a small stitch on the outside.