This is especially for John who posted below regarding a crossbill with an injured wing found at Glen Isla on Christmas day.
The best bet would be to contact the local SSPCA officer - phone 01224 581236.
I am not willing to give out my personal email on the web for obvious reasons, but you can private post me your email via Bird Forum and I will get back to you. I am 'Griffin' on Bird Forum. I can phone you instead if you wish.
We have a really good vet up here at Huntly, Lawrence Brain, who takes in injured birds - I gave the SSPCA an exhausted Fieldfare a few years ago and they passed it on to Mr. Brain where it made a full recovery and was released.
Regarding the Crossbill, is the wing broken ( drooping by side) or is it just strained (can't take off) ? I can possibly get it to someone who rears crossbills ( under DEFRA licence) via a colleague but I would have to come and collect it, or you would have to bring it to me in Aberdeen. They are notoriously difficult to feed in captivity from what I understand, and it will need fluids ASAP. Best bet is local vet in the short term just to keep it alive. Make sure you at least make water available to the bird ( in a saucer/very small container like that for pakora sauce) and you could try sunflower seeds, but I doubt it will eat them.
Would have to examine it to tell you what species - unlikely to be Parrot, but possible ! A Deeside ringed Common Crossbill recently turned up at Lintrathen so please check to see if it is either metal ringed (probably right leg) and /or colour ringed (both legs).
Good luck !