Old dogs learn new things very well, even in a new environment. I like the book "101 Dog Tricks" It is step by step and has great illustrations. My 10 year old pit picks up the tricks faster than my nine month old pup.
that book is awesome! i love it! Totally look into it.
as for old dogs learning new tricks, the question isnt whether they can or not, its whether they want to. Our male Riley is 6.5 years old. He has made it perfectly clear he has no interest in learning new tricks. As far as he's concerned he's learned enough and would rather just lay around chewing on bones and playing the occassional game of fetch. I'm sure your new addition would be content being a loved family member but it may also be exciting to her to learn something new. Perhaps like fetching the a newpaper or a soda from the fridge or something. Maybe even helping you take your clean clothes out of the dryer and putting them in a basket? Thats the next trick i'm wanting to teach Shasta after she masters the pick up command.
Shasta GSD 5/5/10 CGC, ITD, TC
"Dax" Thor z vom Weberhaus BCAT CAX2 CGCA ETD HCT NCO-1 PKD-T RATI RATN RA TC TKA 3/18/2013
"Hades" Guilty vom Blutfeuer 10/26/2018
Zena GSD 6/1/03-2/16/2016
Riley GSD/BC 1/10/05-2/1/2013