like, What's a good shop to buy them?

Should I contact the goverment for any reason?(I mean I know roots can sometimes be a problems)

What Type?( I live in a tempret region)
Feel free to add anything else I should know.

My granddad always advised to dig a $20 hole for a $10 tree. I doubt you can get a tree for $10 these days but you get the idea. Proper preparation of the hole is the most important part of the planting. Check with you local Horticulture extension agent for hand outs and good local advice.