Coleen,
There are quite a few free programs that will take multiple PDFs and combine them into one. I have used stand alone ones quite a few times but have never been happy with online ones.

Let me know if you have trouble getting one and I'll hunt mine up. It's been a while since I used it but it was fast. You can change the order of joining and I'm pretty sure it will handle landscape and portrait in the sam epdf.

cheers,
Erik