Me challenging myself to purely purchase second-hand goods has once again hit a bump in the road with my recent purchase of a bookshelf at the thrift shop.

The bookshelf itself is fine, it looks nice, it was cheap at $25 CAD, and doesn't seem to have any damage to it. However, what wasn't advertised was the fact that the three shelving pieces taped together that rested on top of the shelve in the middle, uhhh, didn't have the holes drilled in yet that would allow for me to attach them to the rest of the unit.

Everything is perfectly fine save for that, so I don't want to toss the bookshelf entirely. If I wanted to prepare the shelving pieces myself to hang them into the adjustable holes, how would I do so? What tools would I need? Since I've never done anything like this before, would this be a good starter project, or should I have someone more experienced do it for me?

Thanks for any help in advance.