First of all, if your wedding is at home then you only need OOT bags for people who are coming from out of town (I know that sounds redundant, but I had a friend who didn't realize and spent a ton buying stuff for no reason). I have been to a bunch of weddings where I got an OOT bag, here are a few of my fav thing:
1. bottles of watter - hotel rooms never have these
2. homemade cookies - obviously you can buy these and package them nicely
3. "things to do" brochure - ie, tourist places to see while in town
4. weekend events - rehearsal dinner, brunch, if any
5. chocolates ('nuff said)