Where can I find actual packing boxes that have no hole in the bottom?
http://www.uline.com/cls_04/Boxes-CorrugatedIf you cannot find what you are looking for online, give them a call to explain your needs. Explain what you are trying to ship before you try to explain the box you want. The box you want may not be the box you need.
Uhaul sells them so does lowes and home depot. lowes is cheapest
ask your local grocery store if they have any banana boxes. they are super sturdy. thats what i use to pack my books and dishes. heavy stuff. those are free
If not buying them try liquor store or grocery store in early morning. Liquor boxes are steardy if they have holes cut another piece to fit the bottom. Copy paper boxes are small but any copy place has them