Wood suitable for outdoor projects (CW8 Barnton)

hello, wondering if anyone can help. Looking for wood suitable for outside projects (old still usable decking, broken down pallet wood, that kind of stuff, maybe even wood from a shed, railway sleepers etc). Need to make some planters / raise beds and some outdoor seating for the mrs. I cnt go out too far, preferably max 15 - 20 mins drive from Barnton please. It would be highly appreciated.