> i love the bulldog breeds,so i was thinking id change breed because i couldnt replace holly with another boxer, i live in scotland and ther doesnt seem to be that many breeders up here.
Travelling is probably going to be necessary - but well worth it for the right breeder and puppy
> should i attend some shows before making a decision on the breeder?
Makes sense to identify a 'type' you like and nice to get some recommendations. Also it's an opportunity to see a couple of different breeds for comparisons. Try Discover Dogs in November if you can bear the trip to London but there are plenty of shows in Scotland too. If you give a location someone on here is bound to be able to tell you what is coming up.
> should i find a puppy on a site like this?
You might find some breeder recommendations on here but it's worth considering joining a waiting list for the right pup. Please don't be tempted by some of the commercial puppy lists, anyone that's spent much time on this site will have heard lots of sad stories about puppy farming and expensive vet bills
> do i ask any specific questions before i make a purchase?
Yes, absolutely. Once you've found the breed you want, research as much as you can about health checks and or problems in the breed. A good breeder will be telling you, long before you ask, about the health checks they do but it makes sense to be prepared.
Finally, think about the things you loved about your boxers. You can ask questions to see how your next chosen breed matches up
Good luck :)