I have a cake due in 3 weeks and the bride wants pinecones, do i try to make them or can i place boughten ones on top that she purchased from craft store... Ive never made them before. Any tips? Thanks!!

Personally, I would not use craft store pine cones.  If you do, I'd place a piece of parchment or wax paper underneath them.  I wouldn't want that to touch the cake.

There are a few tutorials on how to make pine cones...some out of chocolate, some out of royal icing.  I purchased a mold for the pine cones I have done.  I found that easier and I use the mold quite often in the winter :) You could also make your own mold if you'd like to go that route.

there is a pinecone tutorial on this website by (I think) @costumeczar ‍ 

Yes, it's the first one on the list that @640Cake ‍ put up. I'd do them that way, it's not difficult and real ones are dirty and tend to drop little pieces of the cones off.

You can make them out of fondant and then cut the spices with scissors. That's what I did with the trees and it was super easy and fast!

As for how to make them it depends on how big and what icing you want to use.  If b'cream is o.k. and you know how to make a rose you can make pinecones :)  

Thanks everyone  I am going to practice this week and try the royal icing version!