Congratulations! I wish you both the best.

As for cheap ideas, the $1 store or Dollar Tree would be a great place to start for decorations. There is lots of things you can do with their products for very cheap. There are blogs with Dollar Tree crafts that you can check out. Also, check out Pinterest to see some of the ideas that come up there. I'm sure with a combination of the two of them you can come up with some inexpensive, yet classy looking decorations.